IUS ET VERITAS 63

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

https://doi.org/10.18800/iusetveritas.202102.001

The Plea of State of Necessity: A palatable normative

framework for extraterritorial self-defense against Non-

State Actors(*)(**)

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la

legítima defensa extraterritorial contra Actores No Estatales

Moisés Montiel Mogollón(***)

Universidad Iberoamericana (Ciudad de México, México)

Abstract: The UN Charter law governing self-defense is inadequate to address emerging

modalities of armed violence caused by non-State actors located in the territory of

non-consenting third States. This paper o󰀨ers an alternative grounded in the state of

necessity as a circumstance excluding wrongfulness as per the law of State responsibility.

The contention is that in integrating the rationale behind necessity as an excuse for

non-performance of obligations and the conditions and processes under article 51 of

the UN Charter, the law allows for an exercise of extraterritorial self-defense against

non-State actors which safeguards the territorial State’s sovereignty and the need for a

legal alternative of defense for the defending State without toeing the line of aggression.

Keywords: Self-Defense - Non-state Actors - State responsibility - State of Necessity

- United Nations Security Council

Resumen: El régimen de la Carta de la ONU que tutela la legítima defensa es

inadecuado para lidiar con las modalidades emergentes de violencia armada causada

por actores no estatales situados en el territorio de un tercer Estado que no consiente

a intervención. Este artículo ofrece una alternativa basada en el estado de necesidad

como excluyente de la ilicitud de acuerdo con el régimen de la Responsabilidad

Internacional del Estado. La proposición es que, al integrar el razonamiento que soporta

a la necesidad como excusa para el incumplimiento de obligaciones y las condiciones

y procesos existentes en el marco del artículo 51 de la Carta de la ONU, el derecho

internacional permite el ejercicio de legítima defensa extraterritorial contra actores no

estatales que salvaguarda la soberanía del Estado territorial y la necesidad de una

alternativa legal de defensa para el Estado atacado sin cruzar la línea de la agresión.

Palabras clave: Legítima Defensa - Actores no Estatales - Responsabilidad Internacional

del Estado - Estado de Necesidad - Consejo de Seguridad de las Naciones Unidas

(*) Editorial Team note: This article was received on September 2, 2021 and its publication was approved on November 28, 2021.

(**) The author wishes to thank Santiago Vargas Niño and Alonso Gurmendi for their invaluable input in putting this piece together in

record time, and also Ana Soa Vargas for assisting in the research and, in general, for her unlimited patience. Views and mistakes

are the author’s own.

(***) LL.B. (Universidad Central de Venezuela), LL.M. (Fletcher School of Law and Diplomacy, Tufts University). Adjunct Professor of Treaty

Law (Universidad Iberoamericana, Mexico) and Law of Armed Conict (Universidad Panamericana, Mexico). Managing Partner at

Lotus Soluciones Legales (Mexico City, Mexico). ORCID: https://orcid.org/0000-0002-9042-4098. Email address: mmontiel@up.edu.

mx.

16 IUS ET VERITAS 63

Moisés Montiel Mogollón

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

1. Introduction

To the best of current knowledge (Haque, 2021) (Modirzadeh,

2021) there is no normative enshrinement of the right self-

defense against non-State actors operating from the territory

of a third-State without the need for consent of the territorial

State (Paddeu, 2020)(1) that is generally accepted or free from

contestation. As last February’s Security Council Arria-formula

meeting(2) made evident, the articulations of normativity are not

enough in number or magnitude to show a customary extension

of the right enshrined in article 51 of the UN Charter (Montiel,

2021), and State practice is far from general or consistent. The

general position of States on this contention was aptly identied

by prof. Modirzadeh as one of silence (Modirzadeh, 2021). The

result of this is that the Charter law governing self-defense

must be held to operate only among States for the time being.

Seeing as the joint reading of articles 2(4) and 51 of the UN

Charter counterintuitively restrict self-defense to inter-State

exchanges, and despite some ambiguous language by the

UNSC on the issue(3) (Ziccardi, 2007), the fact of the matter

is that self-defense against non-State actors in the territory of

third-State runs counter to the prohibition on the use of force

and is outside of the personal scope of application of article

51. However, if the law governing the use of force fates States

with su󰀨ering attacks under these circumstances with their

hands tied, then, binding as it may be, it becomes a hindrance

in the performance of duties owed to citizens and an enabler

of irregular threats which empties the text and spirit of the UN

Charter and the core principles of modern international law.

Such a position would also be inconsistent with the

expansive caveat included in article 4 of A/RES/3314 (XXIX),

which could be reasonably interpreted to include -to borrow

the language from A/RES/2625 (XXV) as the denition of

aggression does- the inaction or toleration of irregular forces,

armed bands, or mercenaries meaning to violate the territorial

integrity of a third State. Also, the latter document upholds

the duty of a State to refrain “from acquiescing in organized

activities within its territory directed towards the commission

of such [acts of civil strife or terrorist acts in another State],

when the acts referred to in the present paragraph involve a

threat or use of force” (UN, 1975). It is worth noting that the

Annex to resolution A/RES/2625 (XXV) seems to be one of

the likeliest candidates to be considered jus

cogens and thus occupies a place of honor as

far as norms go, as evidenced by the Fourth

Report of the International Law Commission

on Peremptory Norms of General International

Law (ius cogens) on 2019 (International Law

Commission, 2019), and, in any event, it is

an indisputable expression of cornerstone

principles of international law.

From the above observed, the onus seems

to be on the territorial State to prevent and

deter the attack by non-State Actors (NSAs

going forward) upon the threatened State.

This much can be easily inferred. However,

this paper is not concerned with the duty of

the territorial State to avoid irregular armed

bands from inicting damage on the territorial

integrity or the political independence of third

States. It attempts to deal with the question

of resources available to the third State in

question -the recipient of the attack- when

the attack by NSAs is imminent or actual

and the territorial State fails to carry out

its duties to prevent the attack. Surely, the

answer cannot be, as pointed above, that

the would-be victim is powerless to preempt,

halt, or repel the attack. But, then again, such

an action appears to be at odds with article

51, which normatively excludes instances of

self-defense against actors other than States.

What if the answer to this conundrum is not

to be found on article 51 of the Constitution of

the UN, but rather on a simultaneously older

and newer regime?

This piece posits that the breach of

obligations owed to the territorial integrity

and sovereignty of the territorial State where

non-State armed groups can be justied if

the criteria of the state of necessity under the

regime of State responsibility is met. While

some authors opine that the regime of State

responsibility is incompatible with the activity

(1) Notwithstanding some attempts framed as customary law, such as those of the Caroline and Gorostiza Standards, which will be

discussed infra, especially in their allegedly normative dimension.

(2) Dened by the UN Secretariat as “very informal, condential gatherings which enable Security Council members to have a frank

and private exchange of views, within a exible procedural framework, with persons whom the inviting member or members of the

Council (who also act as the facilitators or convenors) believe it would be benecial to hear and/or to whom they may wish to convey

a message. They provide interested Council members an opportunity to engage in a direct dialogue with high representatives of

Governments and international organizations - often at the latter’s request - as well as non-State parties, on matters with which they

are concerned and which fall within the purview of responsibility of the Security Council” (UN, 2021, par. 2).

(3) See UNSC Resolutions S/RES/1373 (2001) of September 28th 2001 and S/RES/1368 (2001) in their preambulatory clauses.

IUS ET VERITAS 63

The Plea of State of Necessity: A palatable normative framework for extraterritorial self-defense

against Non-State Actors

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la legítima defensa

extraterritorial contra Actores No Estatales

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

of the Security Council under the use of force regime, arguing

that the declaration of unlawfulness of a conduct is materially

di󰀨erent than the politic al assessment carried out by the Council

(Tsagourias, 2011), there is no impediment for the UNSC to

incorporate the examination of the operational requirements

for the excuse of necessity into its discussions, a point which

is discussed at large in this paper. This, in keeping with the

logic of articles 24, 39, and 51 of the UNC, which recognize

the organism’s near-monopoly on peace and security issues

and task it with receiving notications of self-defense or any

other situations concerning international peace and security,

acting in accordance with its guarantor role. Additionally, the

composition of the Council and its being bound by international

law would allow incorporation of the requisites laid down by

the ILC’s 2001 Draft Articles on Responsibility of the State

for Internationally Wrongful Acts (DARSIWA going forward) in

assessing whether a state of necessity actually existed at the

moment the counterattacks were carried out and if the breach

is justied and thus not a violation of international peace and

security (and therefore of international law).

In order to answer these questions, this paper is divided into

three sections. The rst one is concerned with analyzing the

shortcomings of self-defense, as enshrined in the UN Charter,

to address the question of how States should respond to attacks

by NSAs on the territory of a third State that has not given its

consent for intervention. In doing so, this section explores the

limits of the inherence and non-constriction features of self-

defense as included in the Charter. It also reviews the existing

debate on the customary law on self-defense and the doctrinal

discussions concerning di󰀨erent standards that enable self-

defense against NSAs (with varying degrees of normativity)

such as the unwilling/unable doctrine and the Caroline and

Gorostiza incidents (and their ensuing doctrines), which have

contributed to shape the customary understanding of the law

of self-defense against NSAs.

The second section seeks to shed light on the institution of

the state of necessity and the current state of the art concerning

the doctrine to test its viability to exclude responsibility for

instances of self-defense against NSAs. To that end, it dissects

the conditions for the operation of the excuse as they have been

codied by the International Law Commission in 2001 and its

reception in international law. This part takes special note of

the relevant dicta of the International Court of Justice which

have substantially shaped the modern understanding of the

exception of state of necessity with a view to provide insights

into the correct interpretation of the requisites of essential nature

of the interest at stake, gravity, and imminence of the threat

that would then justify the breach and preclude wrongfulness.

This with a view to posit the compatibility of the doctrinal and

jurisprudential operation of said requisites with the conditions

of proportionality and necessity that ow from article 51 of the

UN Charter (Kretzmer, 2013).

The third section comprises the pièce de

resistance of this work. It explores how should

the claim of state of necessity operate (with

due regard to the previously laid conditions)

in lieu of the claim of inter-State self-defense

at the UNSC, without discarding the same

requirements of proportionality and necessity.

It also analyzes the issues of the authority of

the Council to entertain such a claim, based on

its primary responsibility for the maintenance

of international peace and security and its

ability to declare any given occurrence as a

threat to international peace and security and

consequently act on it.

The presumptive conclusion of this piece

is favorably oriented towards the legality (and

convenience) of enabling the plea of necessity

before the UNSC as a factor excluding

wrongfulness when actions preliminarily

constituting a breach of article 2(4) must be

taken in order to halt, repel, or maybe even

preempt an armed attack carried out by a NSA

from the territory of a third State, provided

that such a State is not allowing said actions

but refuses to permit the attacked State to

intervene, which leaves the originally attacked

State short of legal options to defend its own

territorial integrity and political independence.

The intention behind this proposition is to

provide a normative framework, compatible

with the law as it currently exists, that can

move the discussion away from contentious

and discretional standards with no normative

traction, such as the ‘unwilling and unable’

doctrine, and to provide a modicum of certainty

for the international community as to when

exceptions to territorial integrity can be

tolerated. In repurposing the UNSC by way of

extension of its material capability to analyze

instances of self-defense against NSAs in the

territory of a third non-consenting State, the

analysis and qualication of any given instance

of use of force becomes simultaneously subject

to legal and political scrutiny and may be held

accountable if it exceeds the limits. At the same

time, it constitutes an honest attempt to curtail

seemingly unfettered conduct by States when

conducting military operations in the territory

of others.

As a forethought, last year, a much

admired countrywoman took the law of

18 IUS ET VERITAS 63

Moisés Montiel Mogollón

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

State responsibility out for a stroll in order to determine

whether consent was “a defense or part of the denition of the

prohibition of force” (Paddeu, 2020), even if the key point of

that piece is only tangent to the discussion proposed here, her

conclusion serves as the perfect starting point of this paper:

any use of force which is inconsistent with the UN Charter

system is illegal and consent (or necessity in this case) is a

defense -or a justication- to exclude responsibility for the

breach. Therefore, and in the interest of safeguarding the

territorial integrity and political independence of the defending

State, recourse must be had to already existing valid law if

self-defense is to be claimed against NSAs in the territory

of a third State without its consent, and the UN Charter and

international law are to be upheld at all.

Additionally, this paper builds substantially on Terry Gill

and Kinga Tibori-Szabó’s paper of 2019, which outlined in

exquisite detail the operation of necessity in the context of the

customary law governing self-defense against NSAs in the

territory of a third non-consenting State. In it, they claimed

that “necessity (…) serve[s] as both the driver and the limiting

function of the exercise of self-defense” (Gill & Tibori-Szabó,

2019). This paper aims to take up the call made by the authors to

provide a normative framework susceptible of providing “some

adjustments” to our current thinking about necessity in order

to make it actionable in the existing Charter system governing

the use of force and self-defense.

2. The inadequacy of Charter

law governing the use of force to

encompass self-defense against

NSAs in the territory of a third State

without its consent

When thinking about the law governing the use of force in

international law, the rules appear to be self-evident. Outside

of UN Security Council (UNSC or the Council going forward)

authorization under a Chapter VII resolution or individual and

collective self-defense, the use of force against the territorial

integrity or political independence of another State, or in any

manner inconsistent with the purposes of the UN is prohibited(4)

(United Nations, 1945) and thus considered an internationally

wrongful act under the label of aggression, pursuant to articles

2(4) of the UN Charter (UNC going forward), and article 5(2) of

General Assembly resolution 3314 (XXIX) of

1974 (United Nations, 1974) which is largely

held to be reflective of customary norms

(Drnas de Clément, 2002) and even of jus

cogens rules (Torp Helmersen, 2014), which

has recently been welcomed into the fold of

international crimes under the competence of

the International Criminal Court.

In fact, article 3 of A/RES/3314 (XXIX)

singles out several actions which fall under

the category of aggression. For example:

invasion or attack of the territory of another

State, bombardment or use of any weapons

against the territory of another State, use of

force exceeding the limits of authorization of

the territorial State when it has consented

to military presence of the attacking State’s

forces, or allowing a State’s territory to be

used by a di󰀨erent State for attacking a third

State, just to name a few (United Nations,

1974). Upon revision a constant becomes

manifest: these banned uses of force are all

conceived as necessarily and exclusively

between States.

The system, dating back to the San

Francisco conference in 1945, was built by and

for States. It has a clear state-centric dynamic

embedded in it (Kotlik, 2017), reective of

the paradigm that governed international law

at the time (Gill & Tibori-Szabó, 2019); the

main (and almost sole) subjects of it were

States. Individuals or private groups were

held to have little or no agency in the legally-

relevant exchanges governed by this branch

of the law(5). As a result, the UN Charter (UNC

henceforth) system governing force does not

take into account the organized used of armed

violence carried out by or against non-State

entities when it is not tolerated or allowed

by the territorial State, which would then

necessarily fall under the ‘domestic matters

of the territorial State’ label to the chagrin of

the threatened or attacked State.

(4) Without prejudice to exceptions created by regional agreements like NATO, or the OAS which largely follow the same logic with

minor deviations. In the case of the Inter-American Treaty of Reciprocal Assistance and its potential application to situations other

than inter-State use of force. See Franck, T. (1970) “Who Killed Article 2(4)? Or: Changing Norms Governing the Use of Force by

States”. American Journal of International Law, 64(5), 809-837, however this point will be revisited later on in this paper.

(5) Except maybe in the realms of international criminal law, international humanitarian law and international human rights law, all of

which were prominent features of the mid-20th century’s legal landscape with the Nuremberg and Tokyo war crimes tribunals and

their ensuing developments.

IUS ET VERITAS 63

The Plea of State of Necessity: A palatable normative framework for extraterritorial self-defense

against Non-State Actors

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la legítima defensa

extraterritorial contra Actores No Estatales

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

Since its inception, the UN’s use of force system was

conceived as a mechanism to sort out disputes between States

that decided to renounce war as means of dispute settlement.

Picking up where the Kellogg-Briand Pact left o󰀨, the San

Francisco Conference of 1945 was inaugurated by President

Truman to the following tune:

(…) The essence of our problem here is to provide sensible

machinery for the settlement of disputes among nations, Without

this, peace cannot exist. We can no longer permit any nation or

group of nations to attempt to settle their arguments with bombs

and bayonets (Truman, 1945, par. 35).

This same spirit, which evidently guided the endeavors of the

San Francisco Conference, is the reection of the commitments

made at Yalta and Dumbarton Oaks (Britannica, 2021). Notice,

in the latter, articles 3 and 4 of Chapter VIII, section A, about

pacic settlement of disputes among States. The intent to

regulate was clear: uses of force between States should be

banned by the future organization to replace the League of

Nations. These commitments were the forebears of the current

UNC use of force system. However, and after more than seven

decades, the dynamics of the international arena have outgrown

the material scope of application of the Charter’s use of force

system by and large.

Interstate armed conflict, whether aggressive or not,

within the meaning of common article 2 of the 1949 Geneva

Conventions, have increasingly become an exceptional

situation. Much in the same way as isolated uses of force

between States falling short of that threshold. This could be

celebrated, partly, as a success of the UN system (if one feels

obsequious) or as a consequence of a myriad other factors

having to do with complex interdependence (Keohane & Nye,

2000). However, conict remains a constant, even if it changes

in formand parties. This observation highlights the apparent

mismatch between Charter law governing the use of force

and current reality, which now encompasses actors other than

States.

Arguably, the reference in article 51 to the non-constriction

of the inherent right of self-defense of States was designed

to respect dimensions of operation outside of the scope of

application of the article itself (Bethlehem, 2021). This would

mean that the scope of customary self-defense at the time of

the drafting of the Charter may have indeed exceeded that of

only interstate uses of force(6). However, as observed by Gill and

Tibori-Szabó (2019), several authors argue that the limitation

implied by the wording of article 51 UNC was deliberately

intended to reduce the scope of action of self-defense even

beyond the Charter(Tladi, 2013). As pointed out: “[o]ne of

the controversies regarding the e󰀨ect of the

Charter on the pre-1945 right of self-defense

concerns NSAGs and whether these groups

can qualify as authors of an armed attack”

(Gill & Tibori-Szabó, 2019, p. 475).

The question raised by the authors

follows the logic of broadening the material

and personal scope of application of article

51 to see whether the right of self-defense

can encompass armed attacks by NSAs.

Even with the diverging opinions of scholarly

commentators on the matter, the application

of interpretation methods enshrined in the

Vienna Convention on the Law of Treaties of

1969 (VCLT) on articles 31-33 would seem

to foreclose such attempt. The Charter is

an international treaty signed by States and

incapable of producing obligations outside of

that personal scope. More to the point, the

travaux préparatoires of the UNC are clear

evidence that:

[T]he drafter’s primary objective was to regulate

State behavior rather than address the dangers

posed by NSAGs. Accordingly, during the

drafting process, the principal discussions

regarding article 51 centered on the concerns

of Latin American States that the Charter and

the powers of the Security Council did not

supersede their regional arrangements for

collective self-defense (Tibori-Szabó, 2011,

p. 474).

Similarly, the personal scope of

applicability of article 51 was not discussed

during the San Francisco Conference. As Gills

and Tibori-Szabó report, an earlier draft of the

article included the precision that it referred to

attacks by a State against any other member

State, but it was later dropped without a

reason on the record for it (2019). This silence,

while in and of itself not terribly indicative of

anything, allows for context to be brought to

bear on account of the lack of literal or textual

interpretations to be had. Thus, systematic

interpretation forces the reader to address

article 51 in the context of article 2(4) of the

same document. In the latter, the use of force

is prohibited among States, and it would stand

to reason that, being the exception to article

(6) This idea certainly nds support in pre-existing doctrines and standards concerning uses of force against non-State actors in the

territory of third States such as those laid out in the Rainbow Warrior case, or the Caroline and Gorostiza Incidents. The ensuing

standards will be explored in more depth later on the piece.

20 IUS ET VERITAS 63

Moisés Montiel Mogollón

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

attacks occurring in the territorial jurisdiction

of the attacked State.

Another point to consider by those

defending a parallel customary regime allowing

for the claim of self-defense tantamount to

that of article 51 UNC is the Charter’s non-

supersession clause located in article 103.

In principle, this rule would preclude the

possibility of change in the terms laid out in the

Charter by any other international agreement

which would then negate the legality of the

so-called parallel customary regime if it runs

counter to the exclusively inter-State domain

of article 51. However, there is contention

on whether article 103 UNC is applicable

to customary law or whether it only applies

to international agreements understood as

treaties (Glennon, 2001) which would render

this particular argument inconclusive, but still

worth considering.

Regardless of the conclusion on the

interpretive discrepancy of article 103 UNC,

another line of defense that would go against

the possibility of both the enlargement of

article 51 UNC by way of practice and against

the existence of a stand-alone customary

permission. This would be the purported jus

cogens nature of the prohibition of the use

of force (Torp Helmersen, 2014). While the

determination and e󰀨ects of jus cogens rules

are still hotly contested (ILC, 2016), one thing

is clear: no norm of jus cogens character may

be derogated from unless such modication

comes from a subsequent peremptory rule.

Naturally, this would apply squarely should

the contending norm be found in a treaty (as

per article 53 VCLT), which is notably not the

case here, nevertheless it is still noteworthy

that there is resistance by the normative

establishment to accept changes to rules

endowed with such superior character(9).

Building on this, the last few years have

witnessed the resurgence of the so-called

2(4), article 51 would inexplicably have a wider ratio personae

spectrum, this same reasoning is exhibited by authors such as

Mary Ellen O’Conell (2013), and Rona & Walla (2013).

A State-centric reading of the result of the joint reading of

articles 2(4) and 51 of the UNC, in line with the freedom principle

enshrined in the PCIJ’s Lotus Case (1927), would thus mean

that if not explicitly prohibited, then the resort to self-defense

against NSAs in the territory of a third non-consenting State

would be lawful (Gill & Tibori-Szabó, 2019). However, upon

close examination, this view doesn’t hold. This is because any

use of force conducted against a NSA will necessarily occur on

the territory of a third State(7) and will then amount to a violation

of article 2(4) UNC in prejudice of the territorial State unless an

exception or justication can be proven.

This latter point also ts within a teleological reading of the

UNC. The object and purpose of article 51 in the larger context

of the UNC is evident from article 2 of the Charter, which lays

out the principles of the Organization. The very object of the

treaty is to preempt uses of force against the territorial integrity

and political independence of member States. The discrepancy

between the target of the attack (the NSA and not the State)

and the e󰀨ects, forcibly su󰀨ered by the territorial State, don’t

appear to be distinguishable, even if the case has been made

by authors such as Trapp (Trapp, 2015)(8). The problem with

using intentionality of targeting as a rationale for toleration is

that it results impossible to ascertain from an objective model

of responsibility, such as the one prevalent in international law.

One further avenue to analyze whether the use of force

system of the UNC can cater to the situation under study is

that of subsequent practice (under the VCLT as complementary

and subsidiary method of interpretation) relative to UN Charter

law (Gill & Tibori-Szabó, 2019). As is usual in these instance,

scholarly commentary covers both positions. In the a󰀩rmative,

authors such as Murphy (2002) and Antonopoulos (2008) posit

that the pre-Charter customary admissibility of self-defense

against NSAs in the territory of a third non-consenting State

remains untouched and therefore, while separate from the UN’s

use of force system, the exercise of self-defense is legal. This

is unconvincing insofar as it adds nothing to consider in the

evolution of practice surrounding the UN Charter but rather just

o󰀨ers the existence of a parallel and unconstrained customary

regime. Another shortcoming of this position is that it does not

take into account the location of the NSA and covers only those

(7) With the potential exception of uses of force carried out in res communis places such as the High Seas or Outer Space, which -on

account of lack of regulation in one case, and lack of potentiality, in the other- are excluded from the analysis of this piece.

(8) The main point of this proposition is that self-defense against NSAs may be permissible to the extent that the territorial State itself

is not targeted.

(9) In its 2019 report on peremptory rules of general international law of the ILC, the Special Rapporteur, Mr. Dire Tladi, has put forth the

notion that jus cogens rules may not be derogated by contravening custom or desuetude. While the author remains unconvinced with

the identication and operation of this special category of norms, it is noteworthy that institutions which do support it are convinced

that these norms may not be derogated from under any circumstances.

IUS ET VERITAS 63

The Plea of State of Necessity: A palatable normative framework for extraterritorial self-defense

against Non-State Actors

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la legítima defensa

extraterritorial contra Actores No Estatales

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

‘unwilling or unable’ doctrine on the realm of jus ad bellum.

While articulations along the same lines can be found as far

back as 1970 by the Nixon administration in the US (Heller,

2019), 1976 by Israel on its Entebbe raid (O’Connell, 2019), or

1981, again by Israel, concerning its armed activities in Lebanon

(Gill & Tibori-Szabó, 2019), it has become prominent in the post

9/11 world and especially in the context of the so-called ‘War

on Terror’ that followed the invasion of Afghanistan. It also was

(even if not mentioned out loud) the preponderant subject of the

above mentioned Arria Formula meeting convened by Mexico

on February 2021.

The ‘unwilling and/or unable’ proposition is built upon the

premise that the territorial State has an active duty to prevent

any damage caused to third States originating on its own

territory, following on the ICJ’s Corfu Channel Case (ICJ, 1949)

recognition of the international obligation not to cause or allow

harm to other States, which is also enshrined in A/RES/2625

(XXV) of 1970 as pointed out above. Thus, the doctrine posits

that “a victim state has the right to engage in lawful extra-

territorial self-defense when the host state is unwilling and/or

unable to mitigate or suppress the threat posed by domestic

NSAs” (Williams, 2013, p. 620).

The doctrine allegedly nds its pedigree as an update

of the Caroline standard (DeLaurentis, 2021), although this

genealogy is a bit doubtful (Heller, 2019). It originally posited

that anticipatory self-defense against NSAs, in order to be

lawful, should comprise “a necessity of self-defense, instant,

overwhelming, leaving no choice of means, and no moment

for deliberation” (Webster, 1837). Precisely because of the

immediacy of the action required and its overwhelmingness

and gravity. The doctrine was held to be a lawful exception to

the then-not so absolute prohibition on the use of force and

went on to constitute the foundation of the customary law of

self-defense in the pre-Charter era.

However, in trying to expand the material reach of application

of the Caroline test to justify the ‘unwilling and/or unable’

doctrine, even if taking into account other relevant incidents

like the Gorostiza standard which notoriously centered the

discussion around the need to prove necessity before allowing

extra-territorial self-defense (Gurmendi, 2020), the test of time

has been unfavorable towards the exception. The paucity of

general practice seems to belie the notion that it has attained

customary character (Chachko & Deeks, 2016), much in the

same way that the invocation of the exception has been all but

consistent (Gill & Tibori-Szabó, 2019). Additionally, it is riddled

with ambiguities which threaten international

peace and security in the absence of clear

regulation. The appreciation put forth by

Sharma and Agarwal hits the mark when they

comment that the eet utile of the doctrine

is to circumvent the need to obtain the host

state’s consent. This can naturally threaten the

international order absent a strict regulation

(Sharma & Agarwal, 2020). The authors

further posit that the doctrine -due to its

inconsistent invocation and application- has

failed to garner customary status (Sharma &

Agarwal, 2020).

The ‘unwilling and/or unable’ doctrine

presents a perfect example of why trying to

articially expand the limits of article 51 UNC is

incompatible with the legal regime laid out by the

treaty itself. The arguments put forth by States,

such as France, Denmark, Egypt, Lebanon,

Colombia, Uganda, or India, doubting the

legality of the doctrine is highly telling (Chachko

& Deeks, 2016) in that they situate Charter

law as the starting point for any discussion

on self-defense, which then complicates any

attempt at enlarging the scope of application

(personal and material) of article 51 UNC. These

sentiments are echoed and expanded further by

States such as Mexico (who convened the Arria

Formula meeting), who have outright rejected

the legality of the doctrine on the same basis

(De la Fuente, 2021).

On the camp of those who argue against

the legality of claiming self-defense in terms

of article 51 UNC as a right to be exercised

against NSAs located in the territory of a third

non-consenting State, the arguments put forth

by Kunz (1947), Stahn (2003), Kammerhofer

(2007) and Orakhelashvili (2015) ring most

persuasive. In sum, these authors support the

conclusion that the use of force system built

into the UN Charter was designed exclusively

for inter-State exchanges of violence(10) and

thus negate the possibility of self-defense

being a feasible or legal claim in the particular

instance of scrutiny of this paper.

(10) With the notable inclusion of instances of armed attack carried out by non-State actors only if attribution or substantial involvement of

a State can be proven. This scenario has been the subject of ample discussion and has been endorsed by the International Court of

Justice in rulings like the Nicaragua case (Nicaragua v. USA) and the Armed Activities case (DR Congo v. Rwanda). In both instances,

the Court has found that if there is a su󰀩cient level of control or involvement of the State in the activities of the armed group then

the actions may be attributable to the State for determination of international responsibility.

22 IUS ET VERITAS 63

Moisés Montiel Mogollón

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

of an attack is not a State, but the o󰀨ense still

originates within the territory of another State

and must be dealt with in its territory. However,

all is not lost. There is law outside of the UN

Charter (and compatible with it) that may be

used for this exact purpose, without prejudice

to the system of use of force contained inthe

treaty. Enter in the ILC’s Draft Articles on

Responsibility of the State for Internationally

Wrongful Acts article 25: the plea of necessity.

3. The state of necessity

as a circumstance

precluding wrongfulness

under the law of State

responsibility

As a forethought to this section, it should

be noted that in the case under analysis,

there is no adequate or materially coincident

regulation (conventional, customary, or

otherwise) that caters to the specic situation

of exercising any type of self-defense against

NSAs located in the territory of a third State

that refuses permission to deal with the

threat. As shown above, Charter law and its

customary equivalent governing the use of

force do not provide sensible alternatives to

this situation. In absence of any regulation in

primary rules, the default option(12) becomes

the Draft Articles on the Responsibility of

the State for Internationally Wrongful Acts

(Crawford, 2019).

Furthermore, before addressing the

proposition of the plea of necessity in the

context of the DARSIWA as a more deft way

to navigate instances of self-defense against

NSAs in the territory of a third non-consenting

State than conventional self-defense in the

Charter context, it is useful to note (as detailed

above) that diverse attempts have been made

to provide frameworks to enable the practice.

Most notable from the academic trenches is

the discussion started by Daniel Bethlehem

In practice, the United Nations Security Council, tasked

with qualifying the legality and correctness of instances of self-

defense under article 51 UNC, has been less than receptive to

claims of self-defense against NSAs in the rare opportunities

when it has said anything at all. Resolutions S/RES/273 of 1969,

S/RES/294 of 1971 dealing with this exact claim being put forth

by Portugal or resolutions S/RES/265 of 1969, S/RES/313 of

1972, or S/RES/467 of 1980 concerning the alleged exercise of

extra-territorial self-defense by Israel bear witness to the little

sympathy the Council holds for this position. However, as will

be noted below, the agency of the Council as a law-determining

body remains contested and the politics that are an integral

part of its operation make it di󰀩cult to ascertain whether the

rejections is founded on politics or on law.

On a similar note, and (mostly) unburdened by the cloud of

politics, the ICJ has also observed that it does not look kindly

to the claim of self-defense under article 51 UNC when used

against non-State actors. In the Wall advisory opinion and

the Armed Activities ruling, the ICJ displayed discomfort with

applying the right of self-defense to non-State attacks lacking

a clear connection to a State (Arimatsu & Schmitt, 2021). This

would conrm that, in the Court’s opinion, the claim of self-

defense under article 51 of the UNC is restricted to inter-State

exchanges of force(11).

As shown above, and recognizing that the issue has

warranted substantial discussion, it’s safe to say that caution

advises against the legality of claiming self-defense when the

author of the attack is not a State. Much more so if the purported

actions to repel, halt, or preempt the attack are to have e󰀨ects

or be carried out in the territory of a third State that has not

consented to the action and regardless of whether the territorial

State has complied with its duty to not tolerate or harbor NSAs

hostile to the defending State.

That is, of course, a matter of law, which, as pointed out

earlier, runs counter to logic and to the defending State’s

own right to the respect of its territorial integrity and political

independence. As a matter of fact, the proposition that the

defending State’s hands are tied, and it is fated to su󰀨er the

attack out of respect for the territorial integrity of the territorial

State is entirely antithetic to its legitimate expectations under

article 2(4) UNC and also absurd.

The conclusion then, is that Charter law governing self-

defense is largely inapplicable to situations where the author

(11) In the interest of precision, it must be annotated that the ICJ, in the Wall opinion and the Armed Activities Case, has only condemned

instances of self-defense carried out against the State harboring the NSAs and not the NSAs themselves. However, this position

could be held to reinforce the impossibility to separate the personal and territorial aspects of self-defense against NSAs in the territory

of a third non-consenting State, as pointed out above. Additionally, the silence of the Court as to this specic situation (which it did

not include as a lawful option) should be read in keeping with the integrity and superiority of the prohibition of the use of force in

substantive terms.

(12) Especially since the articles restrict their applicability if the particular material regime contains any lex specialis dealing with declaration

of responsibility.

IUS ET VERITAS 63

The Plea of State of Necessity: A palatable normative framework for extraterritorial self-defense

against Non-State Actors

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la legítima defensa

extraterritorial contra Actores No Estatales

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

and hosted by the American Journal of International Law of the

so-called ‘Bethlehem Principles’ (Bethlehem, 2012). Su󰀩ce it to

say that the best argument against Bethlehem’s proposition is

that it has failed to generate cohesion among States who nd

themselves attempting to justify their attacks on the territory

of third States (even if bits and pieces of the argument appear

sparsely every now and then in di󰀨erent doctrinal enunciations).

The most cogent expression of the inadequacies of that

proposition is that:

[D]espite their constant invocation, the notions of necessity,

imminence, and proportionality are fraught with conceptual

ambiguit y and are notoriously di󰀩cult to apply in practice. By relying

heavily on necessity, imminence, and proportionality, Bethlehem

imports these di󰀩culties into his principles (Akande & Lieänder,

2013, p. 569).

The criticisms to this proposition are not exclusive to

Bethlehem’s principles. As noted above, neither State practice,

expert commentary, nor even jurisprudence have so far come

up with a regime well-suited and properly tailored to cater to this

very particular situation. That is, presumably, the reason why

exercises like the Arria Formula meeting convened by Mexico in

February 2021 are simultaneously so useful and so problematic.

The lack of clarity and precision ailing the components of self-

defense, in the context of its invocation against NSAs, make it

impractical and cumbersome and di󰀩cult to assess even after

the fact.

This paper contends that self-defense (be it within the

Charter context or without) is ill-suited to answer to the new

realities a󰀨ecting the current conventional and customary use

of force dynamics. As observed earlier, this normative gap

would force the conclusion that States are fated to su󰀨er harm

when the particular conditions studied here present themselves.

Within the very context of the ILC’s Draft Articles, article 21

covers self-defense as a ground for exclusion of responsibility,

but as it was mentioned before, that system is designed for

inter-State instances of self-defense and therefore does not

govern the specic case analyzed in this situation, this becomes

evident in comment (5) of article 21 of the DARSIWA which

claims that “(5) The essential e󰀨ect of article 21 is to preclude the

wrongfulness of conduct of a State acting in self-defense vis-à-

vis an attacking State. (…)” (ILC, 2001). This occurs because the

rules concerning self-defense in the Articles essentially copy the

Charter system of self-defense. In fact, the reference to article

51 UNC is explicitly built into article 21 of the DARSIWA, as is

the subjection to the requisites of proportionality and necessity

under the UN Charter law.

As a matter of legal logic, claiming self-defense when

the author of the attack is not another State creates issues

of contradiction with article 2(4) of the UN Charter. If one

State’s right of self-defense is exercised, then there is a

necessary infringement upon the right of territorial integrity of

the territorial State. Simply put a defending

State cannot repel, halt, or counter an attack

launched by an NSA on the territory of a

third State without exercising force in the

territory of that State and therefore breaching

its territorial sovereignty. This because the

UN Charter bars self-defense against actors

other than States. This ies in the face of

Aristotle’s logical non-contradiction principle,

where two opposing premises cannot be

simultaneously and entirely true. This is

precisely why self-defense is designed

as an exception to the right of territorial

integrity of the territorial State (when it is

itself the attacker) which has opened up to

the infringement by virtue of its own violation

of the other State’s right to territorial integrity

or political independence. The resemblance

to countermeasures is, evidently, uncanny.

This is because it is the aggression of the

attacking State that gives way to the right of

self-defense of the defending State. That is,

however, not the case when attacker is not a

State. The ILC espouses a similar logic in its

commentated version of the Draft Articles. It

goes on to say:

(1) The existence of a general principle

admitting self-defense as an exception to

the prohibition against the use of force in

international relations is undisputed. Article 51

of the Charter of the United Nations preserves

a State’s “inherent right” of self-defense in

the face of an armed attack and forms part of

the denition of the obligation to refrain from

the threat or use of force laid down in Article

2, paragraph 4. Thus, a State exercising its

inherent right of self-defense as referred to in

Article 51 of the Charter is not, even potentially,

in breach of Article 2, paragraph 4 (ILC, 2001,

p. 24).

Read in the context of article 21 as a

whole (especially in its’ 5th and 6th comments),

this exclusion of breach can only operate

when the hostile act occurs amongst States.

Given that self-defense is an exception to

the unlawfulness of the use of force, such an

exception may not be expanded absent the

clear intent to do so on the part of States. To

date, this issue is hotly contested as shown

above, and no clear articulations of opinio

juris su󰀩cient in number seem to exist, as

the coverage of February’s Arria Formula has

conclusively shown.

24 IUS ET VERITAS 63

Moisés Montiel Mogollón

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

The inadequacies of self-defense under Charter law and its

copycat in article 21 of the DARSIWA yield no useful answers

to the question of self-defense against NSAs operating from the

territory of a third non-consenting State. However, a sensible

alternative may -as promised at the outset of this piece- be found

in article 25 of the DARSIWA covering the plea of necessity.

The article in question reads:

Article 25. Necessity

1. Necessity may not be invoked by a State as a ground for

precluding the wrongfulness of an act not in conformity with an

international obligation of that State unless the act:

(a) is the only way for the State to safeguard an essential interest

against a grave and imminent peril; and

(b) does not seriously impair an essential interest of the State or

States towards which the obligation exists, or of the international

community as a whole.

2. In any case, necessity may not be invoked by a State as a ground

for precluding wrongfulness if:

(a) the international obligation in question excludes the possibility

of invoking necessity; or

(b) the State has contributed to the situation of necessity (ILC,

2001, p. 80).

As observed by Arimatsu and Schmitt, “[n]ecessity is a

core principle of international law that operates in diverse ways

within di󰀨erent legal regimes. For example, it is a condition

(the law governing the use of force), a foundational principle

(international humanitarian law), a limitation (international

human right law), and a legal defense (international criminal

law)” (Arimatsu & Schmitt, 2021, p. 1182). Being a core principle

of the normative system, its existence prior to its inclusion in

the 2001 DARSIWA is pretty much uncontested by both the

International Court of Justice and the ILC (Arimatsu & Schmitt,

2021) and by scholarly commentary at large. Evidence of its

role in international law can be found as far back as Grotius,

who wrote of its operation in the context of jus in bello (Boed,

2000), or -in the context of self-defense- in instances like the

Caroline incident or the Gorostiza Pamphlet (Gurmendi, 2020).

In its modern sense, the ILC o󰀨ers a denition of necessity

in the context of justications in the following way:

(1) The term “necessity” (tat de ncessite) is used to denote those

exceptional cases where the only way a State can safeguard an

essential interest threatened by a grave and imminent peril is, for

the time being, not to perform some other international obligation

of lesser weight or urgency. Under conditions narrowly dened in

article 25, such a plea is recognized as a circumstance precluding

wrongfulness (ILC, 2001, p. 24).

Note how, from the outset, necessity is

presented by the DARSIWA as a negative

formulation. This gives credit to its extremely

exceptional nature (Paliouras, 2016) which

has also been noted by the World Court

on its Gabcikovo-Nagymaros Project case

when it highlighted its very exceptional

character (1997). The wording utilized by

the Commission certainly conrms its last

resort nature, not unlike the one that would

be made under circumstances so grave

that left no moment for deliberation and no

choice of means. This exceptional nature

is compatible with the pacta sunt servanda

owed to third States and is precisely why it

makes for a palatable way to navigate the

situation presented in this paper.

From its debut in classical law systems and

to this day, the state of necessity is indicative

of the general unlawfulness of the action taken

in the specic context in a logic akin to that

of justications or excuses (Paddeu, 2020).

However, recourse to it is justied insofar as

it seeks to protect a more valuable interest

than the one being harmed. Boed writes in

this context that:

[W]hen a threat to self-preservation arose,

it was considered justified to take any steps

necessary to preserve one’s existence,

even if such steps would have been unlawful

had they been taken in the absence of a

threat to self-preservation (Boed, 2000,

p. 4).

As observed by the same author, “the

balancing test in the provisionally adopted

text of article 33 of the ILC’s Draft Articles

on State Responsibility is designed to weigh

inconsistent interests of two States (…)”(13)

(Boed, 2000, p. 3), from there it follows,

that the drafters of the articles identied the

norms of State responsibility as exible in

deference to essential interests of States

without necessarily making them trump

cards that would void of content and binding

character the obligations of the State vis a

vis each other.

(13) See also Report of the International Law Commission on the Work of its Twenty-Seventh Session, U.N. Doc. A/10010/Rev.1 (1975),

51-59, U.N. Doc. AICN.4/SER.Al1975/Add.1; Report of the International Law Commission on the Work of its Thirty-Second Session,

U.N. Doc. A/35/10 (1980), 26- 34, U.N. Doc.AICN.4/SER.A/1980/Add.1.

IUS ET VERITAS 63

The Plea of State of Necessity: A palatable normative framework for extraterritorial self-defense

against Non-State Actors

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la legítima defensa

extraterritorial contra Actores No Estatales

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

Its outstanding character has to do with its linkage, in classical

times, to the innate right of self-preservation which is natural

to every State. In fact, Boed (2000), goes on to note that Hugo

Grotius himself accounts for the recognition of the right to self-

preservation as far back as roman law, and that it was later picked

up by the social contract writers such as Locke, Hobbes, and

Rousseau. Thus, the historical logic behind the state of necessity

is not to remove the unlawfulness of the action taken, but rather

to shift the discussion towards the necessity that justies the

illegality in a particular factual context. As a consequence of this

shift in the terms, responsibility for the trespass cannot be exacted

by the aggravated party because of the extraordinary nature of

the threat or harm caused to the State claiming the operation of

necessity. This is consistent with the nature of international law

as a system of voluntary self-limitation (Jellinek, 1880) enshrined

in the Lotus Principle (PCIJ, 1927).

However, not every whim of the State can fall under this

normative exception and the reach of necessity has been

narrowly dened ever since its Grotian inclusion. Rodick

identies six conditions in the writings of the seminal scholar

for the exception of necessity in the context of inter-State

warfare: (1) absence of criminal intent, (2) existence of

real danger to vital interests, (3) temporal imminence, (4)

proportionality, (5) consideration to the equities involved, and

(6) duty to e󰀨ect reparations whenever possible (Rodick, 1928).

Much of these still permeate the ILC’s modern conception of

the state of necessity and resonate with the doctrinal requisites

imposed on self-defense -as an exercise of the fundamental

right to self-preservation of the State- under the aegis of

article 51 of the UN Charter, even if they’re not legislated into

the requisites.

It is precisely because of this higher normative threshold

that it seems to o󰀨er a framework that is simultaneously

respectful of the legitimate expectations of the territorial

State to have its rights under article 2(4) UNC respected while

enabling a non-condemning alternative for the defending State

when an attack by a NSA physically situated in the territory of

the ‘attacked’ State occurs. In raising the bar by demanding a

stricter scrutiny of the existence of necessity, the defending

State need not be hopelessly subject to attacks by NSAs

without being able to see to its own essential interests in the

face of an uncooperative territorial State. In the same train of

thought, it should be noted that the ILC’s 5th comment under

article 25 references the Caroline incident and qualies it not

as self-defense, but rather as a clear-cut case of the operation

of the state of necessity (ILC, 2001) which

is exactly the claim put forth by this piece.

3.1. The conditions for operation of article

25 of the DARSIWA

The forcible conclusion (or perhaps the cause)

of the very existence of the state of necessity as

a circumstance that precludes wrongfulness,

is that it safeguards “the most important of

these fundamental rights of States [which is]

that of existence, which involves the rights

of self-preservation and defense” (Hershey,

1927, p. 231). This is perfectly aligned with

the ontology of the exception in that it seeks

to protect essential interests of the State

that may run counter to its obligations and in

detriment of the rights of other States. In order

to achieve this, necessity requires a balancing

of protected rights against those that would

su󰀨er from the breach.

This is precisely the quid of the issue, as

observed by Boed, “the balancing test in the

provisionally adopted text of article 33(14) of the

ILC’s Draft Articles on State Responsibility is

designed to weigh inconsistent interests of two

States (…)”(15) (Boed, 2000, p. 4), from this it

follows, that the ILC drafters meant to codify

a exible regime, simultaneously mindful of

the most important interests of States without

negating the e󰀩cacy of international obligations.

Fenwick describes the di󰀩culties of the

balancing test in writing that “[t]he conict of

international rights thus resulting is governed

by a few general principles of law, which are,

however, so vague as to leave it an open

question in many cases whether the right

of one has justied a breach of the right of

the other” (Fenwick, 1965, pp. 142-143).

This is exactly applicable, letter by letter, to

the current law governing self-defense and

even more so to the question of whether

self-defense is admissible vis a vis non-State

actors in the territory of a third non-consenting

State, with one minor caveat: the defense of

essential interests of the State, like survival,

is not understood in the context of the law of

(14) Now article 25.

(15) See also Report of the International Law Commission on the Work of its Twenty-Seventh Session, U.N. Doc. A/10010/Rev.1 (1975),

51-59, U.N. Doc. AICN.4/SER.Al1975/Add.1; Report of the International Law Commission on the Work of its Thirty-Second Session,

U.N. Doc. A/35/10 (1980), 26-34, U.N. Doc.AICN.4/SER.A/1980/Add.1.

26 IUS ET VERITAS 63

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Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

responsibility as a right(16), but rather as a way to evade the

responsibility that accompanies the breach of obligation (Ago,

1980).

Ago’s conclusion that self-preservation is -operationally-

an excuse rather than a right is seemingly backed by judicial

practice (Cheng, 2006) and by a noteworthy lack of substantial

State protest.

Notwithstanding the rough edges in its denition, at least

there’s widespread agreement on the requirements necessary

for the plea of necessity to operate. These are laid out in article

25(1)(a) of the DARSIWA and are composed of (1) the essential

nature of the protected interest, (2) the gravity of the harm

threatened or inicted, and (3) the need of immediate action.

From among these three requirements, the rst one poses

severe challenges in terms of interpretation. The ILC itself

declined to provide a denition or a metric of comparison as to

what constitutes an ‘essential’ interest (ILC, 2001). This lack of

denition ought to be interpreted as a deference to the subjective

classication of the State, and as a function of the di󰀩culty to

agree on a xed set of situations meriting such a classication.

The preference for the case-by-case analysis of each scenario

lends credence to the idea that the nature of ‘essential’ of the

interest is context-dependent and should be thus assessed. This

deference to the State is not, however, without limits. The ILC

has opined that “[t]he extent to which a given interest is essential

depends on all the circumstances and cannot be prejudged. It

extends to particular interests of the State and its people, as

well as of the international community as a whole” (ILC, 2001).

In other words, while the burden of proving the essential nature

of the interest is on the claimant of the necessity, the analysis

of whether the interest is fundamental must be carried out in

light of the context and circumstances surrounding the situation.

The dangers in this position are manifold. It opens the door

for pronouncing virtually anything as an essential interest and

therefore negating the extraordinary character of the plea of

necessity. Regardless, the very fact that the essential nature

of the interest ought to be demonstrated in order for the claim

of necessity to hold, provides a much stricter standard than

that of the law governing self-defense, where any armed

attack satisfying a minimal degree of gravity will warrant lawful

retaliation(17). This is already a rst positive for necessity as a

normative framework to complement the law governing the

use of force in the UNC context. Precisely

because of its exceptional nature and the need

for an interest above mere topical allegations

of sovereignty to be demonstrated, it o󰀨ers

-at least- a chance for differentiated and

strict scrutiny where self-defense cannot.

Additionally, the fact that the argument for the

essential character of the interest ought to be

put forth after the unlawful act does not, at

all, subtract from the usefulness of it. By any

metric, if the essential nature of the interest

threatened or attack is not proven, then the

justication fails and the action is outright

illegal, with the necessary consequences

ensuing, much as it can happen when a

claim of self-defense under article 51 UNC is

brought to the UNSC.

As to the second and third requisites

codied by the ILC, namely that of the gravity

and imminence of the peril, the Commission

went on to add that:

Whatever the interest may be, however, it is only

when it is threatened by a grave and imminent

peril that this condition is satised. The peril

has to be objectively established and not merely

apprehended as possible. In addition to being

grave, the peril has to be imminent in the sense

of proximate (ILC, 2001, p. 83).

While these conceptual contributions from

the ILC surely are useful in ascertaining the

limits of operation of the state of necessity,

they contribute little to actually dening what

gravity and imminence are. The exact legal

meaning and import of those two words is the

subject of several rivers’ worth of ink courtesy

of scholarly writing and then some more

brought by international jurisprudence(18).

If self-defense claims under article 51 of

the UN Charter may be used as a mirror for

the operation of the plea of necessity when it

concerns response to armed attacks by NSAs

(and the contention here is that they can to a

certain extent), then to look for orientation on

(16) Which it may very well be, if seen as a function of delegated sovereignty as suggested by modern contractualists (Dobos, 2011)

and also as a consequence of the designation of self-defense as an inherent right under article 51 of the UN Charter. That point is,

nevertheless, besides the scope of this article since the operation of the regime of State responsibility characterizes this right as an

excuse to evade responsibility and not as a ‘‘clash of rights’’.

(17) As occurs with virtually any letter addressed to the Security Council concerning an article 51 notication where mention to the events

that triggered the exercise of self-defense are typically never discussed and, at best, barely mentioned in passing.

(18) Specically on the subject of imminence, the very existence of incredibly robust volumes of results for any search for “preventive

self-defense” or “anticipatory self-defense” bear witness to the diverging views concerning the necessary temporal threshold of a

threat in order for measures to be available to the threatened State.

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The Plea of State of Necessity: A palatable normative framework for extraterritorial self-defense

against Non-State Actors

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la legítima defensa

extraterritorial contra Actores No Estatales

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

the requisites of gravity and imminence the emphasis should

be put on the proxy concepts of necessity and proportionality

because of their intimate relationship. The rationale behind

the likening of these requisites ows from the notion that the

gravity and imminence of the peril provide the metric to assess

the necessity and proportionality of the response in a sort-of

symbiotic normative relationship. If the peril or threat is minor

or trivial, then any armed response to it will necessarily be

disproportionate. If the threat cannot be objectively assessed

to exist, then the response is unnecessary(19).

As the ICJ observed in the Wall opinion, under the UN

Charter any armed attack by another State triggers the right

of self-defense (ICJ, 2004). Regardless of this the Court

has occasionally analyzed whether the original use of force

constituted a grave violation of article 2(4) giving way to the

exercise of self-defense and accordingly qualied the necessity

and proportionality of the defensive force employed. By doing

this, the Court has provided -maybe without actively meaning

to- a judicial standard to qualify both the gravity and (to a lesser

extent) the imminence of the peril that would then trigger the

right of self-defense (or the plea of necessity here). Note that

in the Oil Platforms case the ICJ was unpersuaded by the

US’ arguments concerning the obiter on the use of force and

ended up nding that the US’ actions were neither necessary

nor proportional under the circumstances as appraised by

the Court, which surprisingly enough, engaged in a scrutiny

seemingly more akin to the plea of necessity under the

DARSIWA than that of self-defense, As hinted by Taft, the Court

seemed to suggest that unless a minimal threshold of gravity is

evident in the use of force, then self-defense will not become an

option because it would be unnecessary and disproportionate

(Taft, 2004). Similar conclusions were reached by the Court in

the Armed Activities on the Territory of the Congo case, it found

that the preconditions for the exercise of self-defense were not

satised and, in consequence, it was not tasked with analyzing

whether Uganda’s actions were necessary or proportionate

(Damrosch, Henkin, Murphy, & Smit, 2009).

On the specic issue of imminence, the ICJ understood in

Gabckicovo that the temporal scope need not be materially

and temporally immediate but rather proximate or objectively

foreseeable (ICJ, 1997). As the ILC noted, the clear

establishment of the objective existence of the peril based

on reasonably available evidence at the time of the infringing

measure is enough to open the way for the claim of necessity

(ILC, 2001).

As is evident, the analytical framework of the factual test

needed to ascertain the validity of the claim of necessity is

actually fairly stringent, albeit highly context-

dependent. The best proof of the exceptional

nature of this justification is to be found

precisely in its application by the international

judiciary and arbitral tribunals. As noted by the

Commission in its 14th commentary to article

25 there is ample evidence of the claim of

necessity being submitted to international

tribunals in order to elude responsibility (ILC,

2001) and, consequently, a display by those

many judicial and arbitral instances of a very

rigorous scrutiny of the factual underpinnings

that uphold the validity of the claim (Paliouras,

2016).

The ICJ -again in the Gabcikovo-

Nagymaros Project case- provided useful

theoretical insights in order to check whether

the plea of necessity (as codied by the ILC)

could apply to any given situation. It wrote:

In the present case, the following basic

conditions (...) are relevant: it must have been

occasioned by an “essential interest” of the

State which is the author of the act conicting

with one of its international obligations; that

interest must have been threatened by a

“grave and imminent peril”; the act being

challenged must have been the “only means”

of safeguarding that interest; that act must not

have “seriously impair[ed] an essential interest”

of the State towards which the obligation

existed; and the State which is the author

of that act must not have “contributed to the

occurrence of the state of necessity”. Those

conditions reect customary international law

(ICJ, 1997, paras. 51-52).

If with the enunciation put forth by the

ILC, the Court seems to develop pretty much

the same standards in a more articulated

and demanding way. The requisites for the

claim of necessity to hold, according to the

Gabcikovo bench are (1) the threat or harm

to an essential interest of the State, (2) the

existence of grave and imminent peril, (3) the

lack of less harmful alternatives, (4) the lack

of prejudice or harm to the essential interests

of the State to which the original obligation

was owed, and (5) the lack of contribution to

the peril by the claimant of necessity. These,

(19) It would be intellectually dishonest, however, to simply lump both sets of requisites together without disclaiming that the threshold

for the application of UNC article 51 is the occurrence of an armed attack by another State, which is exactly the very requisite that

this piece seeks to elude to avert the defenselessness of the attacked State when the author of the attack is a NSA.

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do not diverge greatly from the ones included in article 25 of the

DARSIWA except for the lack of a less damaging option. In this

context, the di󰀨erence does not warrant too much explanation

because if there were a less harmful option, then the claim of

necessity (be it under the DARSIWA or under the standard set

by the ICJ) would be precluded from operation because the

infringement was not really necessary. As noted by the ILC,

the course of action taken must be the only way available to

safeguard the imperiled interest. The plea of necessity would

then be excluded if there are other legal means available, even

if they may be more costly or less convenient as long as they

are lawful (ILC, 2001).

3.2. The compatibility of article 25 of the DARSIWA with

the UN Charter’s article 51

Article 55 of the DARSIWA is clear in indicating that the

articles exist without prejudice to special regimes and become

inapplicable in the face of lex specialis. The ICJ has upheld

this maxim in both the Tehran Hostages case in regards to

diplomatic law and in the Gabcikovo-Nagymaros Project case

vis à vis treaty law. Article 25 of the DARSIWA itself curtly

states that “necessity cannot be invoked if the primary rules

exclude the possibility of invoking necessity”. The latter, of

course, is not the case here. Even if article 51 UNC restricts

self-defense to armed exchanges between States, there is no

explicit exclusion of the invocation of the state of necessity. In

fact, necessity is contained within the very terms of reference

that States claim before the Council in exercising their right

of self-defense.

Rules of conict like article 55 DARSIWA only become

applicable when there is a conict of norms. Namely, when

the content and purpose of rules is contradictory or would lead

to opposing results. That is far from the case with the state of

necessity and the Charter norms on self-defense. Since one

looks at the responsibility of State in safeguarding essential

interests, and the other caters to the admissibility of actions

which would prima facie constitute a breach of interstate peace

and security (and thus, legality), there is no conict evident

between the purposes and texts of the norms.

In support of this, the so-called ‘Vienna rules’ (Bjorge,

2018) contained in articles 31-33 of the Vienna Convention

on the Law of Treaties allow for the harmonized interpretation

of “any relevant rules of international law applicable in the

relations between the parties” in article 31(3)(c). Hence, the

application of article 51 UNC need not exclude (nor should it)

the invocation of necessity under the terms of the DARSIWA

since they’re not incompatible and the former does not explicitly

exclude the latter.

Even more so, the welcoming of the state of necessity

into the fold of Charter-governed self-defense via the

UNSC would cater to an actual need of the international

community by bridging the gap created by

the exclusive interstate nature of article 51

UNC and allowing for self-defense against

NSAs under the watchful eye of the Council,

which can then ensure both the conformity

with international peace and security and,

by way of consequence, with the jus ad

bellum.

In this same train of thought and to quote

Schachter referring to the potential expansion

of article 51 of the UNC, it is true that States

exhibit signicant reluctance to “approve uses

of force under expanded conceptions of self-

defense (…). Such reluctance is evidence of

a widespread perception that widening the

scope of self-defense will erode the basic

rule against the unilateral recourse to force”

(Schachter, 1991, p. 171). However, and as

pointed out several times in this piece, the

alternative to expanded interpretations or

lateral solutions (like the state of necessity)

does not in and of itself threaten to erode the

prohibition against the use of force, but rather

to update it to modern needs arising out of the

ever-changing nature of conict.

To avoid the risks highlighted by

Schachter, the responsibility of scrutinizing

the validity of the claim of the state of

necessity as a stand-in for self-defense in

the case where authorship of the attack

rests on a NSA in the territory of a non-

consenting third State should be entrusted

to institutions capable of answering in real

time (or as close as possible to) and which

have the authority to produce qualications

on the legality and legitimacy of a given

use of the plea of necessity. The rst of

these requirements is a direct function of

the immediacy built into the attack itself and

the need for defense without delay, which is

hardly accommodating with the parsimonious

times the international judiciary takes in

adjudicating claims. The second requirement

proposed goes to the need for a body

capable of simultaneously analyzing both the

legal and political dimensions of the actions

taken when the attack and the response

present themselves. It is for this reasons that

this paper suggest that no better alternative

may be found throughout international law

than the United Nations Security Council.

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The Plea of State of Necessity: A palatable normative framework for extraterritorial self-defense

against Non-State Actors

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la legítima defensa

extraterritorial contra Actores No Estatales

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

4. Operationalizing the state of

necessity as an analogue of article

51 of the UN Charter

Arguably, the main aim of the UN Charter was to establish

“an institutional framework regulating the use of force by

substituting unilateral uses of force with collective ones when

certain situations of necessity, as dened by the system, arise”

(Tsagourias, 2011). But, as noted earlier, the right of self-defense

was left explicit in the text of the agreement in recognition of the

fundamental importance attached to the ability of the State to

preserve itself (Waltz, 1959). However, and as shown above,

this conventional iteration of the right of self-defense was built

on the notion that the only legally relevant uses of forces would

be those conducted between States.

This is perhaps the reason why Tsagourias argues that “[w]

hen a state for examples uses force in self-defense, it asserts a

right; it does not need to invoke necessity in order to justify its

right of self-defense as such” (2011, p. 29) without pondering

that the right of self-defense as enshrined in art. 51 UNC only

covers interstate uses of force and condemns to illegality those

not encompassed under the three exceptions to the prohibition

of article 2(4). Since self-defense against NSAs in the territory of

a third non-consenting State is not included in the exceptions to

the prohibition on the use of force, then it becomes necessary

to nd a legal path to safeguard the essential interest of the

attacked State.

The state of necessity could constitute the legal foothold

necessary to allow for such exercises of self-defense if the

requisites laid out in article 25 of the DARSIWA are met (which

would not be terribly di󰀩cult, as incidents like the Caroline or

Gorostiza have shown).

However, the typical processes associated with adjudication

of responsibility such as bilateral claims commissions or

recourse to judicial or arbitral settlement would belie the

imminence of the situation that triggers the illegality, and thus

condemn the claim to epiphenomenalit y. In this context, the rst

argument for proposing the UNSC as an ideal venue for airing

such claims is one of e󰀩ciency: The reporting duties stemming

from article 51 UNC and State practice provide the perfect

vehicle for alerting the Council when force is used against an

NSA in the territory of a third State that has not consented such

an action (regardless of its position vis à vis the NSA). The

best proof of this is that States are already doing it even if the

legality of the use of force is still up for debate, as the recent

Arria Formula Meeting of February showed.

There are many counters to the argument of using the UNSC

as an ideal venue for the examination of whether necessity

justies the attack against the territorial integrity and sovereignty

of the territorial State from which the NSA operates. Kelsen points

out the root of the most prevalent ones by

noting that the UNSC’s role “is not to maintain

or restore the law, but to maintain or restore

peace, which is not necessarily identical with

the law” (Kelsen, 1950, p. 294). Tsagourias

follows him in pointing out that the measures

adopted by the UNSC “can be coercive or

non-coercive, but they are not equivalent to

legal consequences as in the law of state

responsibility” (Tsagourias, 2011, p. 30).

Thus, the most pervasive arguments against

the idea of this paper lie within the realm of

the ‘political character’ of the decisions of the

UNSC. These will be addressed by o󰀨ering one

simple rebuttal: politics -such as those of the

UNSC- don’t exist in a vacuum, much less so

in international law where all ability is derived

from State concession. Even while being

preeminently political in its’ daily operation, the

Council is bound by international law and its

par excellence a venue where the currency is

law (even if it serves as a dressage for politics)

(Johnstone, 2003). The Council constantly

makes legal, and it seems a disservice to

articially separate ‘peace and security’ from

‘rule of law’.

In those few instances where the Council

has in fact reprimanded uses of force for being

aggressive, such as the Israeli bombing of

the Osirak reactor, its answers are deeply

embedded in legal terms and cause legal

consequences. In the majority of cases

where it has been silent, its inaction cannot

and should not be equated with tolerance or

legality (that is precisely where its political

nature shows itself). It is this very uidity that

has enabled the Council to procure a measure

of success in its task, but it by no means

signies that it is precluded from carrying out

legal analyses and assigning consequences

to illegal conducts. In short, politics and law

can and do mix, even if they mostly don’t at

the seat of the Council, which by no means

entail that they can’t. As an example of

this, note how the Council has the power to

qualify a use of force as aggressive under the

terms of the UN Charter and aided -among

others- by the denition of aggression. Is

that not, perchance, a most pure form of

legal determination of responsibility as a

consequence of a juridical qualication of any

given action?

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4.1. The role of the UNSC in qualifying the validity of the

exception

If then, the claim of state of necessity is legally feasible in

order to exempt a State from responsibility when it conducts

attacks against a NSA in the territory of a non-consenting

third State, the next pressing question is about the logistics

of such a claim: would the UNSC be legally competent to

determine the existence and validity of the alleged state of

necessity plea?

The most tempting and straight-forward answer would be

that the State who has su󰀨ered the injury to its sovereignty

and territorial integrity (assuming it is an unwilling host of the

NSA and that it refuses to invite the originally attacked State

to intervene on its behalf) should have recourse to judicial

settlement as stated in article 33 of the UNC. However, if viewed

from the perspective of the State su󰀨ering the attack carried

out by the NSA, this makes little sense both in temporal and

logistical terms. Firstly, it would lack jus standi to make any

claims (not being the aggravated party on account of being

unable to show harm caused by another State); secondly,

the institution of proceedings before international tribunals is

anything but expedite (which would then render pointless the

situation of urgency and imminence of the attack), and lastly, it

completely ignores the likely reticence of the defending State to

have its actions submitted to judicial scrutiny (Gomez & Montiel,

2021). Without prejudice to the submission of the case to the

international judiciary once the dust has settled, there is another

instance that o󰀨ers a much faster and equally legal setting to

analyze the potential claim of necessity in using force against

the territorial integrity of the third State: The United Nations

Security Council.

In its Nicaragua ruling, the ICJ a󰀩rmed without controversy

that any measures taken under article 51 must be immediately

reported to the Council (ICJ, 1986) and that it is tasked with

determining the conformity of the instance of self-defense

with the law governing the use of force between States. The

same is stated by article 51 ejusdem in its second sentence.

However, as noted at the outset of this work, the exercise of

self-defense against NSAs (as di󰀨erentiated from interstate use

of force) seems to be outside of the scope of activity of article

51 (hence the need to have recourse to the law governing

State responsibility). The reason for this is that NSAs are not

States and therefore any armed attack would fail, by reason

of its authorship, to meet the threshold required by article 51

(Gill & Tibori-Szabó, 2019) which would therefore theoretically

negate any obligation of reporting to the Council on the part of

the defending State.

However, this interpretive syllogism is not entirely faithful

to the truth of State practice. As Lewis, Modirzadeh, and Blum

have identied, there is ample practice in the context of the

UNSC of informing the Council when measures are carried out

under self-defense against non-state actors to

the tune of some 118 instances since the year

of 1951 and until 2018 which have involved

instances of self-defense against NSAs or

States and NSAs jointly (Lewis, Modirzadeh,

& Blum, 2019). This has become especially

recurrent in the context of the invasions of

Iraq and Afghanistan in the early 2000’s and

later on with the measures taken to combat

the so-called Islamic State of Syria and the

Levant (ISIL/Daesh), it is also a constant for

Israel as a function of its refusal to recognize

Palestine as a State and thereby treating its

government as an NSA.

It could then be argued at face value,

and pending a conscientious review of

concurrence of State practice and opinio

juris, that a customary obligation may exist

or is -at the very least- in formative period,

which extends the duty of reporting measures

taken under article 51 even if the target is

not directly another State (with the ensuing

vicious circle question of whether it really is an

article 51 report or something else). As pointed

out by the ILC, the practice of International

Organizations and of member States within

them can -in principle- constitute acceptable

practice in determining the existence of

rules of customary law (ILC, 2018). This is

further supported by the near-monopoly the

UNSC holds over international peace and

security and its ‘primary’ responsibility in the

maintenance of it. As a consequence, even if

it is not mandatory, the practice of reporting

instances of self-defense to the Council

should be analyzed from the lens of material

reality and the primacy of State practice, as

observed by the ICJ in the Continental Shelf

case concerning Libya and Malta (ICJ, 1985).

From this it follows that States can notify the

Council (even if they’re not explicitly obligated

to) of any measures taken under the aegis of

self-defense against NSAs in the territory of

a third non-consenting State.

If they can do so in respect of article

51 measures, would itnot be the same hold

largely true if the allegation were not one of

self-defense but of a permissible violation

of article 2(4) UNC excused by the state of

necessity in the supra referenced terms? The

argument here is that they are in fact allowed

to do so as a function of identity in nature

IUS ET VERITAS 63

The Plea of State of Necessity: A palatable normative framework for extraterritorial self-defense

against Non-State Actors

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la legítima defensa

extraterritorial contra Actores No Estatales

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

and purpose of the claim in a teleological reading. As noted

earlier, article 51 is an exception (inherent and inalienable as

it may be, but exceptional nevertheless) to the prohibition on

the use of force against the territorial integrity and political

independence of the aggravated State, therefore, the legal

usefulness of claiming self-defense is to exclude the possibility

of labelling the measures as incurring in the use of aggressive

force. The same rationale applies for claiming the existence

of a state of necessity to justify the adoption of measures that

would otherwise violate article 2(4) UNC.

The e󰀨ect of the validity of such a claim is precisely the

erosion of unlawfulness of the action, in the intelligence that the

preservation of essential interests of the State is at play here

and thus warrants the commission of a prima facie unlawful act.

The conclusion is that it would be arbitrary and senseless to

distinguish between a claim of force being used in self-defense

under article 51 UNC and one of state of necessity made under

article 25 of the ILC’s DARSIWA since these two are motivated

by almost identical circumstances (armed attack by another

State and armed attack by a NSA), seek to safeguard the same

essential interests (even if the threshold required by article 51

UNC is lower in that any armed attack by another State warrants

self-defense and the claim of state of necessity would require

demonstration of the specic essential interest in jeopardy),

and have the same e󰀨ect (exempting the classication of the

measures taken as violations of article 2(4) UNC).

Thus far, it is evident that States can report to the UNSC

the measures adopted against the armed attack carried out by

an NSA justied under a state of necessity, because they do. It

has also been shown that the Council is competent to receive

such a notication since the activity falls squarely under the

category of ‘international peace and security’, but then the most

important question arises: does the UNSC possess the power

to qualify the validity and legality of such actions?

Even with respect of de jure article 51 communications, the

Council rarely responds o󰀩cially to self-defense notications.

Bearing in mind that if the UNSC reaches the conclusion that

a particular instance of self-defense fails to conform to the

parameters emanating from article 51, the forcible conclusion

would be that such an action constitutes a breach of article

2(4) UNC. However, nowhere in the law are declarations of

responsibility automatic or self-executing, and the law governing

the use of force is no exception. In this context, the UNSC

would have to formally declare the existence of a breach of

international peace and security as indicated by article 39

UNC and then proceed to declare responsibilities and/or award

reparations. Nevertheless, this is seldom the case with the

UNSC. In most instances, the Council opts for silence, in some

other select ones it has chosen non-condemnatory language

ordering the re-establishment of the previous status quo, and

only exceptionally has it outright qualied an action carried out

under the shadow of article 51 UNC as illegal.

As noted by Sievers and Dawn this variable

practice pursuant to article 51 is compounded

by the fact that the UNSC typically avoids

determinations as to the self-defense nature

of an action reported to it (Sievers & Daws,

2014). However, the fact that it doesn’t qualify

does not entail (by and large) that it can’t.

The practice of the UNSC in dealing with

communications concerning self-defense has

been mostly of silence (Lewis, Modirzadeh,

& Blum, 2019), with the notable exception

of S/RES/487 (1981) dealing with the Israeli

preventive strike against the Osirak reactor in

Iraq and a handful of others. Thus, it is safe to

conclude that the Council rarely qualies the

legality of allegations of self-defense (Kerr,

2012). This silence can be read in several

ways. On the one hand, given its mandate

to monitor and uphold international peace

and security, the silence of the Council when

presented with an article 51 communication

can be read as a conclusion of lawfulness

(Quigley, 2003) much in the same logic that

silence creates acquiescence under certain

circumstances. It has also been posited

that silence can amount to mere toleration

without necessarily conveying acceptance

or lawfulness (Orakhelashvili, 2015), or

alternatively one could argue that no legally

relevant e󰀨ect should be deduced from the

inaction of the Council (Montiel, 2021) as “a

handful of States cannot speak for all States,

and it is improper to infer agreement from

silence“ (Glennon, 2001, p. 75). Regardless

of this, article 51 UNC calls for an ex post

control of the conformity of the measures

adopted by the defending State and it is

patent that the Council can and should answer

as a matter of law. This is the exact same

holding of the ICJ in its Nicaragua ruling,

later upheld in the Oil Platforms Case (ICJ,

2003), in which the Court found the UNSC to

be competent to determine lawfulness of the

whose justication is sought on the basis of

self-defense. In this intelligence, the answer

is almost obvious, even if the Council is not

a judicial organ, it is required by the Charter

to analyze the conformity of any action taken

under article 51 UNC with the law governing

self-defense and use of force in general.

More to the point, if the Council is tasked

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(20) Also note how the Council occasionally dabbles in quasi-judicial exercises with the Al-Qaeda Sanctions Committee and in would-

be normative practices when it issues thematic resolutions like s/res/1882 (2009), none of which have been met with protest from

Member States, which would then o󰀨er the reasonable assumption that such a behavior from the Council is -at least- not ultra vires.

with receiving article 51 UNC communications and qualifying

the legality of the use of force therein exerted, possesses the

competence to declare the existence of a breach of international

peace and security, and has the primary responsibility for the

maintenance of international peace and security as per article

24 of the UNC, alongside with the power to adopt any decisions

it deems necessary for the restoration of international peace

and security (such as declaring the illegality of any given use of

force), then the doctrine of implied powers as put forth by the ICJ

in its Advisory Opinion concerning Reparations for Damages

Suered in the Service of the United Nations (ICJ, 1949) would

force the conclusion that the Council needs to have such a

power in order to carry out its responsibilities e󰀨ectively(20).

Nevertheless, authors such as Klabbers have argued

against such a notion claiming that the UNSC is inherently

political in nature and should not be deemed to have the

power to determine juridical situations (Klabbers, 2015). This

conclusion seems to run counter to the bona de interpretation

of the UN Charter and the relevant dicta of the ICJ concerning

the law governing the use of force. The fact that it is a political

body in nature need not necessarily compromise the legitimacy

of juridical determinations the Council may reach in qualifying

the legality of self-defense, it may even enrich it by virtue of ‘the

power of the better argument’ (Johnstone, 2003) and because

the of political counter-weights present in the Council under the

guise of technical arguments based in the law.

This goes to show that the Council can in fact determine the

legality of measures taken under article 51 UNC. If the same test

of identity applied a few paragraphs ago is applied here, there is

no reason why the Council would be precluded from entertaining

a debate on the legality of measures adopted against an armed

attack of a NSA justied in a state of necessity. It would, after

all, be an act susceptible of constituting breach of article 2(4)

of the UNC and would therefore merit the Council’s attention

with a view to determining whether or not such use of force is

aggressive. This in turn, falls under the purview of the Council

without the need of any further analysis.

Solid evidence for this possibility, is provided by article 2 of

A/RES/3314 (XXIX) which states that “the Security Council may,

in conformity with the Charter, conclude that a determination

that an act of aggression has been committed would not be

justied in the light of other relevant circumstances”. While

the cited text is in the negative, it does reveal that the Council

may look to external circumstances (such as the existence

of a state of necessity) in determining whether a given use

of force constitutes an act of aggression under article 2(4) of

the UNC. In fact, it is this same article 2 of

the denition of aggression resolution of the

General Assembly that utilizes the language

of justication to preclude illegality (bearing in

mind that aggression is clearly illegal under

Charter law and a breach of a myriad of

international obligations), and thus signals to

the compatibility of the regime of excuses in

analyzing uses of force as per the DARSIWA.

Nor does it warrant further scrutiny the

question of whether the Council may analyze

the validity of the claimed state of necessity

on the part of a State countering an attack by

an NSA. The UNSC has no xed parameters

(other than necessity and proportionality) to

determine whether the use of force in self-

defense is legal or not, but can -and always

does- look to the UN Charter, and general

international law for guidance. In this context,

it is especially noteworthy that necessity is

already built into the criteria for assessing

the legality of measures adopted in self-

defense, as was held by the World Court in

the Oil Platforms case (ICJ, 1986), what the

here proposed solution would entail is merely

providing a more structured scrutiny of the

necessity requirement in order to preclude

the wrongfulness of the use of force against

the territory from where the NSA operates.

The notion entertained here is, of

course, one concerned with possibility and

competence of the Council. A di󰀨erent one

-and perhaps more pressing- is whether the

Council (and the member States of the UN)

will entertain such claims. The answer to such

a question would necessitate member States

bringing the claim forth and seeing if, in being

demanded a determination, it will oblige.

There is nothing to suggest that the practice

of the UNSC wouldn’t evolve to meet such

requirements if pressed to by the membership

of the Organization in the search for a viable

alternative to being fated to su󰀨er damage as

a consequence the unwillingness or inability

to foresee this modality of violence back when

the UNC was being drafted.

IUS ET VERITAS 63

The Plea of State of Necessity: A palatable normative framework for extraterritorial self-defense

against Non-State Actors

El Alegato de Estado de Necesidad: Un marco jurídico digerible para la legítima defensa

extraterritorial contra Actores No Estatales

Revista IUS ET VERITAS Nº 63, diciembre 2021 / ISSN 1995-2929 (impreso) / ISSN 2411-8834 (en línea)

5. Conclusions

As reality has shown, the particular mode of political violence

that occurs when NSAs use the territory of a third State (with or

without its toleration) to launch armed attacks against another

State is not a new phenomenon and is, presumably, here to

stay. An international law which fates the attacked State to such

su󰀨ering is not one particularly coherent with the principle of

sovereign equality and also one that fails to recognize that the

State, and its sacred duty to protect its territory and people,

are at the center of the normative order. Therefore, it stands to

reason that the law would -by omission or lack of foresight- bind

States to su󰀨er such attacks without remedy.

This article has shown that, unless clear indicated

otherwise, the law governing the responsibility of the State for

internationally wrongful acts is applicable to the rules governing

self-defense (in the context of the use of force regime) when

the author of the attack is not a State but an NSA. Additionally,

the identity in object and purpose (and requisites of operation)

of both regimes would render arbitrary any attempt to bar the

application of the state of necessity to the situation where an

NSA attacks a State from the territory of a third State that fails

to honor its duty to prevent damage from its territory to the

defending State.

The realization that -although theoretically constrained by

the interstate dynamics of the UN Charter- the UNSC has near-

absolute monopoly on the scrutiny of the use of force by States

should caution that attempting to divert such a competence is

an exercise in wishful thinking. The powers and attributions of

the Council have grown over the years because the realities of

politics and law have demanded it (and because States rarely

protest the decisions of the Council because it acts on delegated

authority from all the members of the UN). After all, the Council

is little more than the voice of its members (Hurd, 2018) and

its politicized application of the law is -to the chagrin of many

observers- an inescapable feature of the use of force system.

In this context, the argument against allowing the Council to

examine the claim of necessity when defending against the

attack of an NSA from the territory of a third non-consenting

State on the grounds of its political nature would certainly raise

questions as to why such an examination is not questioned when

the participants of the exchange of violence are only States.

As annotated above, Schachter (1991) cautioned against

licentious interpretations of self-defense that could have the e󰀨ect

of eroding the prohibition on the use of force, in the way that

doctrines like the ‘unwilling or unable’ do. Arguably, this concern

reects the need for strict rules that are not easy to bypass via

semantic sleight of hand on the part of war-prone States. The

proposition of this paper seeks to uphold the spirit of Schachter’s

advice. In importing the rules governing the plea of necessity

and incorporating them into the analytical toolkit of the UNSC,

far from attempting to erode the prohibition

against the use of force, the aim is to strengthen

it and to update it so that it may better serve

its real purpose: guaranteeing international

peace and security in a way that is respectful

of the sovereignty of all States involved without

imposing undue burdens upon them. The idea

is to use already existing law to ll the lacunae

that may be lled, as is the case here.

In a system, such as international

law, which has its origin in the freedom of

States there is a severe di󰀨erence between

self-limitation in the interest of peaceful

coexistence and a shackle impeding the

defense of the population and territory of the

States themselves on account of a normative

oversight of seven decades ago. The claim of

the plea of necessity arbitered by the UNSC

is a legally coherent attempt to turn the latter

into the former in a way that is respectful

of existing law and cautiously deferential to

national sovereignties.

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