Limitations and Rights of Self-Defense under Public International Law

This essay delves into the complexities of Article 51 of the UN Charter, which addresses the right to self-defense for member states. It explores the controversies surrounding this right, particularly in the context of armed attacks, including those initiated by non-state actors and terrorist groups. The essay examines the limitations imposed on self-defense to maintain international peace and security, emphasizing the importance of proportionality, imminence, and necessity. It discusses the interplay between individual and collective self-defense, the role of the Security Council, and the conditions under which the use of force is justified. The analysis covers the definition of armed attack, the doctrines of harboring and substantial involvement, and the potential misuse of self-defense. Furthermore, the essay highlights the significance of adhering to the principles of proportionality, imminence, and necessity to ensure the lawful exercise of self-defense. It concludes by emphasizing that the right to self-defense must be exercised within the boundaries set by the UN Charter and in alignment with the objectives of restoring international peace and security.

Running head: PUBLIC INTERNATIONAL LAW
Public International Law
Name of the Student
Name of the University
Author Note

1PUBLIC INTERNATIONAL LAW
Introduction
Article 51 pertaining to the UN Charter has been subjected to a considerable number of
controversies. This article confers the right upon to the member states of the United Nations
to exercise collective or as well as individual self-defence when they are made to face any
armed attack. However, once the Security Council has adopted measures to combat the same
and to restore the international security and peace, such acts of self-defence needs to be
halted with immediate effect. Any such act of self-defence that the member states might have
exercised in the pursuance of this article needs to be brought to the knowledge of the Security
Council with immediate effect1. Again, this section restricts the member states from
indulging into any such activities under this article, which might have the effect of hindering
any of the responsibility or the power belonging to the Security Council conferred by the UN
Charter that enables the Council to pursue any action that seems necessary for the purpose of
restoring the peace and security of all the nations. There are certain restriction that the rights
acquired through this article might be subjected to for the purpose of ensuring the conserving
the international peace and international security of the nations2. Although the state has been
conferred with the right to use force as self-defence but the same needs to subjected to certain
limitations that Article 51 provides for. The chief objective of such limitation is to ensure the
restoration of international peace3. This essay would analyse this article for the purpose of
assessing the right that has been conferred upon the member states in relation to the use of
self-defence. It would also address the limitations that the right can be subjected to for the
purpose of restoring the international peace.
1 Williamson, Myra. Terrorism, war and international law: the legality of the use of force against Afghanistan in
2001. Routledge, 2016.
2 Higgins, Rosalyn. "The United Nations at 70 Years: The Impact upon International Law." International &
Comparative Law Quarterly 65.1 (2016): 1-19.
3 Shah, Niaz A. "Review article." Islam and the Law of Armed Conflict. An Elgar Research Collection, 2015.

2PUBLIC INTERNATIONAL LAW
Discussion
The right conferred by Article 51 of the UN Charter allows the member states to exercise
the use of force to combat any armed conflicts that they have been subjected to. However,
prior to assessing this right, the identification of the instances which can be treated as armed
conflicts or attacks needs to be assessed. The term armed attack may include any form of
attacks that has been initiated by any terrorist groups or even any non-state actors. However,
for the purpose of this article, the right to self-defence can also be initiated towards a state
who has been extending harbour to any terrorist groups or any non-state actors who are
involved with the exercise of an armed attack4. Any self-defence mechanism that the state
may initiate against such an act of armed attack or even an act of harbouring a group involved
in the armed attack can be said to be justified and lawful. As per the UN charter, the term
armed attack has been provided with a narrow meaning. It has been defined under this charter
as any act of using force, any attack by the use of arms and ammunitions and any act of
aggression that has been posing a threat of immense destruction5. Any such attacks that are
inflicted upon the states need to be treated with use of force by the state in the form of self-
defence. However, such a right to exercise self-defence is only available to a state if the
attack has been initiated from outside. Any internal armed attacks that might have been
inflicted upon the states do not confer upon the state the right to self-defence. This is because,
article 51 of the UN charter extends the right to use of force by way of self-defence only in
the case of external attack and domestic attacks6.
Recently, there has been a considerable increase in the number of instances where such a
right of exercising self- defence has been invoked against any of the armed groups who has
inflicted armed conflicts towards the state invoking the rights and has been taking shelter in
4 Hakimi, Monica. "Defensive force against non-state actors: The state of play." (2015).
5 Dworkin, Anthony. Europe's New Counter-terror Wars. European Council on Foreign Relations, 2016.
6 Hamid, Abdul Ghafur, and Khin Maung Sein. "Combating Terrorism and the Use of Force against a State: A
Relook at the Contemporary World Order." JE Asia & Int'l L. 8 (2015): 107.

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another states without any direct assistance or consultation being made with that state. The
basic requirements for the purpose of rendering an attack to be an armed attack against a state
have been curbed to a minimum. The armed attack has presently being affirmed to the non-
state actors. However, all these have been posing the threat towards the collective security
pertaining to a state7. The aim of centralization with respect to the use of force has been
threatened by the collective or individual self-defence mechanism of the individual states.
The doctrines of harbouring, unintentional and substantial involvements of the states with the
non-state actors have posed a stern threat towards the solidarity of the states in the sense of a
centralized use of force by all the states together8. The armed attacks that has been inflicted
upon the state who has been using the self-defence mechanism by the non-state actors poses a
threat to the state in which the attackers has taken resort to. These states are inflicted with
violence by the state attacked without having any real faults9. These states however, have the
option of resorting to the doctrine of unwillingness and substantial involvement. Again, there
has been a misuse among the states regarding the use of these doctrines to get away with the
intentional involvements. Moreover, the degree of self-defence mechanism that the states are
utilising needs be optimum and is in proportion with the act of violence inflicted upon them.
This can be treated as a misuse of the right of self-defence that has been provided by the UN
Charter10.
There are certain concepts that need to be addressed in a particular instance for the
initiation of self-defence against any groups exhibiting an armed conflict against a state
adopting such a defence mechanism. These three concepts that need to be adhered to for the
7 Brunnée, Jutta, and Stephen J. Toope. "Self-Defence Against Non-State Actors: Are Powerful States Willing
But Unable To Change International Law?." International & Comparative Law Quarterly 67.2 (2018): 263-286.
8 D. Kretzmer, 'The Inherent Right To Self-Defence And Proportionality In Jus Ad Bellum' (2013) 24 European
Journal of International Law.
9 Tsagourias, Nicholas. "Self-defence against non-state actors: the interaction between self-defence as a primary
rule and self-defence as a secondary rule." Leiden Journal of International Law 29.3 (2016): 801-825.
10 de Wet, Erika. "The invocation of the right to self-defence in response to armed attacks conducted by armed
groups: Implications for attribution." Leiden Journal of International Law 32.1 (2019): 91-110.

4PUBLIC INTERNATIONAL LAW
purpose of adopting the measure relating to the self-defence mechanism are proportionality,
imminence as well as necessity11. All these doctrines are required to be adhered to for the
purpose of rendering an act of self-defence to be just and lawful. These doctrines prevent the
states from indulging into acts of using excessive force in the name of self-defence12. In this
context, it can be stated that the use of the right to self-defence is limited to a certain degree.
This degree of violence that the state is allowed to exercise under article 51 of the UN
Charter is required to be assessed from the principles of proportionality, imminence as well
as necessity. Under the doctrine of necessity, the amount of violence that the state who has
been subjected to armed attack can exercise is needs to be in conformity with the severity of
the armed conflict that needs to be addressed by the violence13. The use of violence under this
doctrine is to be justified in the light of necessity of the measures that has been adopted. The
doctrine of imminence is yet another theory that needs to be adhered to while exercising the
right to self-defence. Under this doctrine, the state needs to ensure that the use of self-defence
is inevitable in a given circumstance14. The third doctrine that needs to be adhered by the state
while inflicting violence by way of self-defence is the proportionality doctrine. Under this
doctrine, the violence inflicted by a state against any armed conflict is required to be
proportional with the armed attack that the state has been subjected to. The violence by way
of self-defence should not exceed the severity of the armed conflict that state has been
subjected to15.
The right of self-defence that has been conferred upon the states by virtue of article 51 of
the UN Charter has to be exercised against any use of force subjected to the limitation that
11 Etezazian, Sina. "The nature of the self-defence proportionality requirement." Journal on the Use of Force and
International Law 3.2 (2016): 260-289.
12 Haque, Adil Ahmad. "Necessity and Proportionality in the Law of War." Cambridge Handbook on Just War
(Larry May ed, CUP 2016) (2016).
13 Haque, Adil Ahmad. "14 Necessity and Proportionality in International Law." The Cambridge Handbook of
the Just War (2018): 255.
14 Van Steenberghe, Raphael. "State practice and the evolution of the law of self-defence: clarifying the
methodological debate." Journal on the Use of Force and International Law 2.1 (2015): 81-96.
15 Dapo Akande and Thomas Liefländer, 'Clarifying Necessity, Imminence, And Proportionality In The Law Of
Self-Defense' (2013) 107 The American Journal of International Law.

5PUBLIC INTERNATIONAL LAW
has been provided under other provisions of the UN Charter16. The right to exercise self-
defence is to be carried out in conformity with the customs of necessity as well as
proportionality that prevailed in the previous circumstances. The right to self-defence is only
available to a party if it has been ensured that no action has been taken by the UN or of the
organs of UN or the purpose mitigating the threat to disruption of international peace as well
as security17. The UN has the first priority to initiate an action where there exists any threat to
the world peace. This action needs to be taken by the organs of the UN. In case the state who
has been proposing to initiate an action against any armed attack that has been caused to it
needs to be ensure that such no action has been taken by the UN regarding the same. Once an
action has been taken by the UN against the law armed attack, the state upon whom the
armed attack has been inflicted loses its right under article 51 to use self-defence18. The right
that has been conferred upon a state in relation to usage of violence to combat armed conflict
by way of self-defence needs to be limited to the stringent conditions that have been provided
under the charter. This right of the state needs to be accompanied with the restrictions that
have been provided under article 2(4) of the UN Charter. In case of any armed conflict being
initiated against any state, the state that has been using self-defence has the option of either
bringing an action by way of an attack through the military forces of its own or it can utilise
the assistance and support of other states for the purpose of bringing such a combat19.
The right of the act of self-defence needs to be exercised in a manner which can be
conceived as lawful for the purpose of being recognised in the international law as compliant
with the article 51 of the UN Charter. However, the task of combating such armed attacks is
16 Van Steenberghe, Raphael. "State practice and the evolution of the law of self-defence: clarifying the
methodological debate." Journal on the Use of Force and International Law 2.1 (2015): 81-96.
17 O'Connell, Mary Ellen, Christian J. Tams, and Dire Tladi. Self-Defence against Non-State Actors. Vol. 1.
Cambridge University Press, 2019.
18 Peters, Anne, et al. "Self-Defence Against Non-State Actors: Impulses from the Max Planck Trialogues on the
Law of Peace and War." (2017).
19 Rao, Pemmaraju Sreenivasa. "Non-state actors and self-defence: a relook at the UN Charter Article 51."
Indian Journal of International Law 56.2 (2016): 127-171.

6PUBLIC INTERNATIONAL LAW
conferred upon the UN and the UN is responsible for carrying out such defence mechanism
of the restoration of international peace and security. These states are conferred with the right
to address such act of armed attacks if the same needs to be exercised to the extent to which
the UN has failed to take any actions20. All these actions that has been taken either by the
state or by the UN needs to have an objective of ensuring international peace being restored.
The combat mechanisms should not have the effect and objective of causing or instigating
diversifications. It needs to be limited to the restricting of the armed conflict and not any
further. For the purpose of assessing the legality and the dimension of the act of self-defence,
three aspects needs to be established21. Firstly, the time prior to the initiation of such an
armed attack needs to considered and all the events that has occurred within that timespan
need to be assessed and taken into consideration. Secondly, the events and the time for which
such an act of violence have lived needs to be assessed. Lastly, the effects and the events that
have followed such act of armed conflict needs to be assessed. All these factors needs to be
assessed for the purpose of assessing the severity of the armed attack and for the making the
decision that would require an act of self-defence to be resorted to. Moreover, the
consideration of these factors would also provide the justification of the force applied by way
of self-defence22.
The use of the right to self-defence does not justify the use of force by the nation under the
name of self-defence for the purpose of serving their economic interest. It needs to be
established before any adoption of measure under the scope of self-defence that the conflict
has been severe enough to addressed using the political measures. There needs to be a
prominent evidence of attack being present, which inflicts an impossibility of being
20 Upeniece, V. "Conditions for the lawful exercise of the right of self-defence in international law." SHS Web
of Conferences. Vol. 40. EDP Sciences, 2018.
21 Williamson, Myra. Terrorism, war and international law: the legality of the use of force against Afghanistan in
2001. Routledge, 2016.
22 Green, James A. "The ratione temporis elements of self-defence." Journal on the Use of Force and
International law 2.1 (2015): 97-118.

7PUBLIC INTERNATIONAL LAW
addressed through political or diplomatic means for the purpose of resorting to self-defence
mechanism. Moreover, even if the attack has been evidencing possibilities of posing a threat
to the nation, which cannot be stopped through political instruments and the nation has
already started with the act of self-defence, but the same would be required to be informed to
the Security Council23. Moreover, before the initiation of any of these actions under the name
of self-defence, the sates are required to ensure that no action has been taken by the UN or
any of the organs of the UN for the purpose of addressing such issues. In case the UN has
taken a stand against such an act of violence against any state, the right to use self-defence is
denied to the affected state. However, whether is an act of self-defence or an action taken by
the United Nations, the same needs to be taken with the main objective or restoring
international peace and security. This needs to be given the utmost priority while combating
any such act of violence24.
Conclusion
Hence, it can be concluded that the right conferred by Article 51 of the UN Charter allows
the member states to exercise the use of force to combat any armed conflicts that they have
been subjected to. The basic requirements for the purpose of rendering an attack to be an
armed attack against a state have been curbed to a minimum. The armed attack has presently
being affirmed to the non-state actors. However, all these have been posing the threat towards
the collective security pertaining to a state25. The aim of centralization with respect to the use
of force has been threatened by the collective or individual self-defence mechanism of the
individual states. The doctrines of harbouring, unintentional and substantial involvements of
the states with the non-state actors have posed a stern threat towards the solidarity of the
23 Peter Ørebech, 'UN Charter Article 51 And The Right To ‘Anticipatory Self-Defense’: Validity Of The US
Preventive War Doctrine Against Al Qaeda' (2014) 23 Middle East Critique.
24 Paddeu, Federica I. "Use of Force against Non-state Actors and the Circumstance Precluding Wrongfulness of
Self-Defence." Leiden Journal of International Law 30.1 (2017): 93-115.
25 Brunnée, Jutta, and Stephen J. Toope. "Self-Defence Against Non-State Actors: Are Powerful States Willing
But Unable To Change International Law?." International & Comparative Law Quarterly 67.2 (2018): 263-286.

8PUBLIC INTERNATIONAL LAW
states in the sense of a centralized use of force by all the states together26. Moreover, before
the initiation of any of these actions under the name of self-defence, the sates are required to
ensure that no action has been taken by the UN or any of the organs of the UN for the
purpose of addressing such issues. In case the UN has taken a stand against such an act of
violence against any state, the right to use self-defence is denied to the affected state.
However, whether is an act of self-defence or an action taken by the United Nations, the same
needs to be taken with the main objective or restoring international peace and security. This
needs to be given the utmost priority while combating any such act of violence27.
26 D. Kretzmer, 'The Inherent Right To Self-Defence And Proportionality In Jus Ad Bellum' (2013) 24 European
Journal of International Law.
27 Paddeu, Federica I. "Use of Force against Non-state Actors and the Circumstance Precluding Wrongfulness of
Self-Defence." Leiden Journal of International Law 30.1 (2017): 93-115.

9PUBLIC INTERNATIONAL LAW
Bibliography
Brunnée, Jutta, and Stephen J. Toope. "Self-Defence Against Non-State Actors: Are Powerful
States Willing But Unable To Change International Law?." International & Comparative Law
Quarterly 67.2 (2018): 263-286.
Dapo Akande and Thomas Liefländer, 'Clarifying Necessity, Imminence, And Proportionality
In The Law Of Self-Defense' (2013) 107 The American Journal of International Law
de Wet, Erika. "The invocation of the right to self-defence in response to armed attacks
conducted by armed groups: Implications for attribution." Leiden Journal of International
Law 32.1 (2019): 91-110.
Dworkin, Anthony. Europe's New Counter-terror Wars. European Council on Foreign
Relations, 2016.
Etezazian, Sina. "The nature of the self-defence proportionality requirement." Journal on the
Use of Force and International Law 3.2 (2016): 260-289.
Green, James A. "The ratione temporis elements of self-defence." Journal on the Use of Force
and International law 2.1 (2015): 97-118.
Hakimi, Monica. "Defensive force against non-state actors: The state of play." (2015).
Hamid, Abdul Ghafur, and Khin Maung Sein. "Combating Terrorism and the Use of Force
against a State: A Relook at the Contemporary World Order." JE Asia & Int'l L. 8 (2015):
107.
Haque, Adil Ahmad. "14 Necessity and Proportionality in International Law." The
Cambridge Handbook of the Just War (2018): 255.

10PUBLIC INTERNATIONAL LAW
Haque, Adil Ahmad. "Necessity and Proportionality in the Law of War." Cambridge
Handbook on Just War (Larry May ed, CUP 2016) (2016).
Higgins, Rosalyn. "The United Nations at 70 Years: The Impact upon International Law."
International & Comparative Law Quarterly 65.1 (2016): 1-19.
Kretzmer D, 'The Inherent Right To Self-Defence And Proportionality In Jus Ad Bellum'
(2013) 24 European Journal of International Law.
O'Connell, Mary Ellen, Christian J. Tams, and Dire Tladi. Self-Defence against Non-State
Actors. Vol. 1. Cambridge University Press, 2019.
Ørebech P, 'UN Charter Article 51 And The Right To ‘Anticipatory Self-Defense’: Validity
Of The US Preventive War Doctrine Against Al Qaeda' (2014) 23 Middle East Critique
Paddeu, Federica I. "Use of Force against Non-state Actors and the Circumstance Precluding
Wrongfulness of Self-Defence." Leiden Journal of International Law 30.1 (2017): 93-115.
Peters, Anne, et al. "Self-Defence Against Non-State Actors: Impulses from the Max Planck
Trialogues on the Law of Peace and War." (2017).
Rao, Pemmaraju Sreenivasa. "Non-state actors and self-defence: a relook at the UN Charter
Article 51." Indian Journal of International Law 56.2 (2016): 127-171.
Shah, Niaz A. "Review article." Islam and the Law of Armed Conflict. An Elgar Research
Collection, 2015.
Tsagourias, Nicholas. "Self-defence against non-state actors: the interaction between self-
defence as a primary rule and self-defence as a secondary rule." Leiden Journal of
International Law 29.3 (2016): 801-825.

11PUBLIC INTERNATIONAL LAW
Upeniece, V. "Conditions for the lawful exercise of the right of self-defence in international
law." SHS Web of Conferences. Vol. 40. EDP Sciences, 2018.
Van Steenberghe, Raphael. "State practice and the evolution of the law of self-defence:
clarifying the methodological debate." Journal on the Use of Force and International Law 2.1
(2015): 81-96.
Van Steenberghe, Raphael. "State practice and the evolution of the law of self-defence:
clarifying the methodological debate." Journal on the Use of Force and International Law 2.1
(2015): 81-96.
Williamson, Myra. Terrorism, war and international law: the legality of the use of force
against Afghanistan in 2001. Routledge, 2016.
Williamson, Myra. Terrorism, war and international law: the legality of the use of force
against Afghanistan in 2001. Routledge, 2016.