Ishaan Kulshrestha[i]


Among the topics of contention in public international law, there are few as hotly debated and enduringly relevant as the legality of humanitarian intervention. Objectors of intervention rely on traditional notions of international law such as territorial integrity and sovereignty and cite its potential for abuse. Supporters, meanwhile, deride existing mechanisms for intervention to be too restricting and inefficient, and rely on arguments that include state practice and the shifting nature of international law. Voices on both sides grow louder each time an international crisis like Kosovo or Syria comes along and reminds the world of the burning importance of reevaluating intervention and the use of force. The substantial role of international legal norms in informing state conduct and decision-making has long been established. Therefore, legal recognition of the right to intervene possesses serious material importance for the future of the global order and individuals across the world.

Legal discussions on the use of force and humanitarian intervention emanate from Article 2(4) of the Charter of the United Nations. The statute prohibits the use of force against the “territorial integrity” or “political independence” of any State. Exceptions to this prohibition are the right of self-defence (as mentioned in Article 51) and the principle of collective security (embodied in Chapter VII), which empowers the Security Council to authorise the use of force against a State it deems to be threatening international peace. This article, however, deals with unilateral humanitarian intervention – a humanitarian intervention that is exercised outside the ambit of exceptions provided under the Charter. In other words, it is beyond the explicit justification of self-defence and without the authorisation of a Chapter VII resolution, as has been seen most prominently in Kosovo and Syria. The article argues against the legal recognition of the right of unilateral humanitarian intervention by studying the arguments commonly provided in favour of the idea and refuting each of these arguments.

The Shifting Paradigm of International Law

A common argument brought up by proponents of Unilateral Humanitarian Intervention (‘UHI’) is that the shifting paradigm of international law provides a theoretical basis for the legal recognition of a right of UHI. The shift here refers to the development of international law away from the Westphalian model which emphasised states as their subjects, and towards a modern approach that includes non-state actors and, more importantly, individuals. The shift has renewed the definition of state sovereignty. The increased focus on the individual has ushered in a balance between the interests of men and women and the state, as opposed to the old view, which held the state’s rights to be above individuals’ rights. The sovereignty of the state is now conditional, and brings with it duties to the individual. In cases of grave violation of these duties, international action may be taken. This renewed definition of sovereignty, according to proponents, is conducive to humanitarian intervention outside the authorisation of the UNSC. 

In refuting this argument, it must be addressed whether the nature of sovereignty has been renewed over the years to the extent that it may allow UHI. The fact that international law has developed towards a balance between the state and the individual is undeniable. States now enter international human rights treaties (such as the International Covenant on Civil and Political Rights and the Convention on the Rights of the Child) and subject themselves to international mechanisms of oversight. This is an acknowledgement of the universal nature of human rights as opposed to such rights being the discretion of the state. As a result, international bodies have been empowered to glare through the sovereign walls of states to ensure the meeting of these obligations. What must be noted, however, is that all these treaties and mechanisms arose through the voluntary action of states, whether it be signing the ICCPR or subjecting themselves to mechanisms like the Universal Periodic Review. In the development of the modern paradigm of international law, state consent has always played a role. UHI that precludes the role of the target state violates the principle of state consent, which remains indispensable even in this renewed international law regime, and cannot be justified using the shifting nature of sovereignty as an argument.

Customary International Law

Another major argument advanced for the legal recognition of UHI is based on customary international law. The argument contends that states have been practising UHI before and after the UN Charter. Recent decades have witnessed several major instances of humanitarian intervention outside UNSC authorisation. These include Vietnam’s intervention in Cambodia, the intervention by UK, France and the US in Iraq, and NATO intervention in Kosovo. The crystallisation of a new rule in customary international law requires two elements: state practice i.e. an extensive repetition of an action over time by states internationally, and opinio juris i.e. a consistent and evident belief by states that the concerned act is legally valid. The argument based on customary international law holds that instances like those mentioned above provide the requisite state practiceand opinio juris for UHI to emerge as a rule of customary international law and exist alongside the UN Charter in governing the law on the use of force.

This argument holds no weight either. For the crystallisation of UHI into a rule, there must be a consistent history of states using force to intervene on humanitarian grounds (state practice) unilaterally, and a consistent belief that there is a right of UHI (opinio juris). It is hard to find, in recent history, instances of undisputed UHI with the solely humanitarian intent. An empirical analysis of post- Cold War military interventions revealed self-interest to be the most powerful factor for intervention and concluded that despite the existence of altruism in some cases, self-interest is a constant and solely altruism is never a factor for intervention. Establishing opinio juris is also extremely difficult. Analysing the justifications provided by intervening states in instances of intervention barely reveals any reference to emerging custom or previous state practice. Notably, the NATO states provided differing justifications for intervention in Kosovo, with none citing previous state practice and none even mentioning humanitarian intervention apart from Belgium. Similarly, no justifications based on the legality of UHI were provided for the airstrikes in Syria by participating states other than the UK. Other prominent examples include the ECOWAS’ interventions in Liberia and Sierra Leone, which were justified using the founding treaty of the ECOWAS rather than UHI, and the intervention in Iraq justified by the US as ‘pre-emptive self-defense’. Moreover, the legality of UHI has routinely been rejected by an overwhelming majority of states, as was evident in the 2000 Declaration of the South Summit by the G77 where 130 states explicitly declared UHI to be illegal. Thus, the lack of agreement regarding the legitimacy of UHI causes it to fall severely short of the standards of opinio juris. The case for recognising UHI as a customary rule is further weakened by the precedent of Nicaragua v. United States where the ICJ held that custom does not allow UHI.

Object and Purpose of the UN Charter

Proponents further contend that existing law on the use of force is too narrow to sufficiently address dire humanitarian requirements, and the objects and purposes of the UN must be paid heed to. Objectives mentioned in the preamble of the UN Charter include “to save succeeding generations from the scourge of war” and “to reaffirm faith in fundamental human rights, in the dignity and worth of the human person.” Article 55 also emphasises human rights, calling for their “universal respect” and “observance”. UHI fits into pushing forward these objectives of the UN, and since UHI fulfils these objectives, it is also compatible with Article 2(3) of the Charter as the Article only prohibits uses of force inconsistent with the object of the UN.

The Charter’s objectives clearly reflect a tension between human rights, and non-intervention and sovereignty. As mandated by Article 31(1) of the Vienna Convention, however, a treaty must be interpreted “in accordance with the ordinary meaning to be given to the terms of the treaty.” To put it simply, the Charter must be interpreted textually, as prescribed by the Convention, focussing on the text itself rather than speculating upon object or purpose. The Charter explicitly provides only two exceptions to the prohibition of force, i.e. self-defence and collective action through the UNSC. The achievement of any objective of the UN through the use of force must be routed through the mechanism provided by the Charter, as is plain from a textual reading. If the founders of the Charter wished for unilateral force to also be an exception, they would have included it in the text explicitly. Any unilateral use of force is permitted only under the principle of self-defence. Trying to reconcile UHI with Article 2(4) is therefore futile. 

Responsibility to Protect (R2P)

Proponents further point out the emergence of the principle of responsibility to protect (R2P). The principle holds that sovereignty is not absolute, and the state bears a responsibility to protect its citizens from atrocities like genocide, war crimes, and ethnic cleansing. The global community may intervene if a state fails to protect its citizens from such atrocities. Proponents of UHI argue that the failure of the UNSC to act during times of grave concern can provide justification to states to unilaterally intervene on humanitarian grounds under the principle of responsibility to protect.

The responsibility to protect, however, does not necessarily equate to humanitarian intervention. The principle espouses several non-forceful means to protect individuals from atrocities. Military intervention is prescribed by the responsibility to protect only as a last resort, and strictly under the authorisation of the UNSC under Chapter VII of the Charter. The use of the principle as a justification of UHI, therefore, fails as well.


As seen above, there hardly exists a sound legal basis for the acknowledgement of UHI under international law. Unilateral use of force without UNSC authorisation, stands against the principles of collective security and collective action. The recognition of UHI shall grant an excessive license to states to use force against other states by dismissing the authority of the UNSC on the basis of incompetence. Problems certainly exist within the existing framework with respect to addressing an urgent humanitarian need. The veto power in the UNSC, for example, can often sound the death knell for attempts at any humanitarian action, as has been seen in the repeated vetoing by Russia and China of resolutions to deliver humanitarian aid to Syria. The solution, however, lies in tackling these problems and reforming the mechanisms of the UNSC rather than in unilateral violence.

[i] Ishaan Kulshrestha is a third-year law student from Jindal Global Law School.