The UN Charter Article 51 provides for the inherent right of self-defence against any use of force as an exception, which is otherwise prohibited under Article 2(4). Exercise of right of self-defence is however subject to customary law requirements of necessity and proportionality. It is considered operative only until and otherwise subject to any ‘action’ the UN Security Council is empowered to take in case of threats to peace, breach of the peace or act of aggression under Chapter VII of the Charter. The UN Charter of 1945 envisaged use of force only among States, but did not expressly limit its application only to such cases. Given this fact, considerable authority now exists to treat use of force by non-State actors as prohibited under Article 2(4) on par with the ‘armed attacks’ by regular armed forces giving rise to the right of self-defence in favor of the targeted States; provided that acts in question are not mere border incidents. This article deals with cases of the ICJ in the light of some contemporary proposals and principles identified as relevant. It also examines issues of State responsibility for wrongful acts of non-State actors operating from its territory, causing injury to third States.
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See, Kashmir attack: India ‘launches strikes against militants’, BBC News (30 September 2016) <http://www.bbc.com/news/world-asia-37504308>.
‘Pakistani authorities have long had ties to domestic militant groups that help advance the country’s core foreign policy interests, namely in connection with Afghanistan and India. Since Islamabad joined Washington as an ally in the post-9/11 “war on terror,” analysts have accused Pakistan’s security and intelligence services of playing a “double game,” tolerating if not outright aiding militant groups killing NATO troops in Afghanistan. Pakistan denies these charges.’ Ashley Tellis, a senior associate at Carnegie Endowment for International Peace, in a January 2008 Congressional testimony laid out five categories of numerous terrorist groups operating in Pakistan: (1) Sectarian: Religiously motivated groups such as the Sunni Sipah-e-Sahaba and Lashkar-e-Jhangvi and the Shia Tehrik-e-Jafria that are engaged in violence within Pakistan. (2) Anti-Indian: Groups focused on the Kashmir dispute that operate with the alleged support of the Pakistani military and the intelligence agency Inter-Services Intelligence, such as Lashkar-e-Taiba, Jaish-e-Muhammad, and Harakat ul-Mujahadeen. (3) Afghan Taliban: The original Taliban movement and especially its Kandahari leadership centered around Mullah Mohammad Omar believed to be based in Quetta. (4) Al-Qaeda and its affiliates: The global jihadist organization founded by Osama bin Laden and led by Ayman al-Zawahiri. (5) The Pakistani Taliban: A coalition of extremist groups in the Federally Administered Tribal Areas, led by Mullah Fazlullah. Tellis quoted in, Zachary Laub, Pakistan’s New Generation of Terrorists, CFR Backgrounders, Council on Foreign Relations (18 November 2013) <http://www.cfr.org/pakistan/pakistans-new-generation-terrorists/p15422>.
See the conclusion on the state of the applicable law at the end of this paper.
See, Bharat H.Desai, Surgical Strikes’ by India Taking International Law Seriously, LII(5) EPW (2017) 21–24.
See KN Trapp, Back to Basics: Necessity, Proportionality, and the Right of Self-Defence against Non-State Terrorist Actors, 56 Intl & Comp L Q (2007) 141–156, 141.
For the Letter of the USA addressed to the UN Security Council, see UN Doc. S/1998/780.
For a discussion of relevant issues and the views of Professors Cassese, Dupuy, Gaja, and Koh, see Disussion Forum, http://www.ejil.org/forum_WTC.
Noting that since 1990 there emerged ‘a small number of rogue states that, while different in important ways, share a number of attributes’. It is noted that these States ‘brutalize their own people and squander their national resources for the personal gain of the rulers; display no regard for international law, threaten their neighbors, and callously violate international treaties to which they are party; are determined to acquire weapons of mass destruction, along with other advanced military technology, to be used as threats or offensively to achieve the aggressive designs of these regimes; sponsor terrorism around the globe; and reject basic human values and hate the United States and everything for which it stands.’ See, the Letter of the USA, Ibid., 14. Noting that it has ‘taken almost a decade for us to comprehend the true nature of this new threat’, it is asserted that, given the goals of rogue states and terrorists, ‘the United States can no longer solely rely on a reactive posture as we have in the past.’ The inability to deter a potential attacker, the immediacy of today’s threats, and the magnitude of potential harm that could be caused by our adversaries’ choice of weapons’ are cited as the rationale to act proactively in a preemptive way before the enemy is allowed to ‘strike first’. Ibid. 15.
‘Traditional concepts of deterrence will not work against a terrorist enemy whose avowed tactics are wanton destruction and the targeting of innocents; whose so-called soldiers seek martyrdom in death and whose most potent protection is statelessness. The overlap between states that sponsor terror and those that pursue WMD compels us to action…The United States has long maintained the option of preemptive actions to counter a sufficient threat to our national security’. Ibid.
On “imminent threat” as a basis for using force by way of the right of self-defense, it is noted that ‘For centuries, international law recognized that nations need not suffer an attack before they can lawfully take action to defend themselves against forces that present an imminent danger of attack.’ It is also admitted that legal scholars and international jurists’ often conditioned the legitimacy of preemption on the existence of an imminent threat- most often a visible mobilization of armies, navies, and air forces preparing to attack’. Ibid.
Letter of the USA addressed to the UN Security Council, supra note 8, Ibid. 16.
Former US President Obama said:
In all our efforts, we aim to draw a stark contrast between what we stand for and the heinous deeds of terrorists. We reject the lie that America and its allies are at war with Islam. We will continue to act lawfully. Outside of areas of active hostilities, we endeavor to detain, interrogate, and prosecute terrorists through law enforcement. However, when there is a continuing, imminent threat, and when capture or other actions to disrupt the threat are not feasible, we will not hesitate to take decisive action. We will always do so legally, discriminately, proportionally, and bound by strict accountability and strong oversight. The United States—not our adversaries—will define the nature and scope of this struggle, lest it define us.
See, <https://www.whitehouse.gov/sites/default/files/docs/2015_national_security_strategy.pdf> 9. For a note on Obama’s approach, see, Christian Gray, President Obama’s 2010 United States National Security Strategy and International Law on the Use of Force, 10 Chinese J Intl L (2011) 35–53.
RB Russel, The United Nations and the United States Security Policy (Brookings, Washington DC, 1968) 47–60, 119–121.
Judge Nagendra Singh said:
In fact this cardinal principle of non-use of force in international relations has been the pivotal point of a time-honoured legal philosophy that has evolved particularly after the two World Wars of the current century. It has thus been deliberately extended to cover the illegality of recourse to armed reprisals or other forms of armed intervention not amounting to war which aspect may not have been established by the law of the League of Nations, or by the Nuremberg or Tokyo Trials, but left to be expressly developed and codified by the United Nations Charter.
Separate Opinion of President Nagendra Singh, in, the Nicaragua case, Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United States of America) Merits  Judgment, ICJ Rep 14, 151. Professor Murty notes that the ‘impermissibility of the use of force by way of reprisals seems to be more or less definitely established at present.’ The author examined various views in this context. BS Murty, The International Law of Propaganda: The Ideological Instrument and World Public Order (New Haven Press, New Haven, 1967) (reissued in 1989) 170–171. For an extensive treatment of the subject of the use of force, see generally, Ian Brownlie, International Law and the Use of Force by States (OUP, Oxford, 1963).
See, Article 24(1) of the UN Charter < http://www.un.org/en/charter-united-nations/>.
Murty, supra note 18, xxvi.
Article 26 of the UN Charter envisaged the establishment of a Military Staff Committee as provided under Article 47 to assist the Security Council to formulate plans and submit them to States to help “regulation of armaments”. It must be underlined that the primary purpose of the establishment of the Military Staff Committee under Article 47(1) is ‘to advise and assist the Security Council on all questions relating to the Security Council’s military requirements for the maintenance of international peace and security, the employment and command of forces placed at its disposal, the regulation of armaments, and possible disarmament.’ To further the scheme of the collective security system thus framed for the maintenance of international peace and security, Article 43 requires all member States ‘to make available to the Security Council, on its call and in accordance with the a special agreement or agreements, armed forces, assistance, and facilities including rights of passage necessary.’
But mostly, the Security Council made ‘declaratory statements confirming the right of individual and collective self-defence without other qualifications.’ Armed attacks of South Africa against Angola (RES.546/84), invasion of Kuwait by Iraq (Res 661/1991) and the terrorist attacks against the USA (1368/2001) are cited as examples. Present Problems of the Use of Force in international Law, the Report of the sub-group on self-defence of the 10th Commission (June 2007); 72 Annuaire de l’Institut de droit International - Session de Santiago, Chili (A. Pedone, Paris, 2007) 75–149, 107 (Hererinafter, Roucounas Report) <http://www.justitiaetpace.org/idiF/annuaireF/2007/Roucounas.pdf>.
On authorization of use of force by the Security Council, see for an authoritative statement of the law and policy, the Resolution adopted by the Institut de Droit International (hereinafter the Institut) at its 2011 Rhodes (Greece) Session <http://www.justitiaetpace.org/idiE/resolutionsE/2011_rhodes_10_%20D_en.pdf>.
On breakdown of the collective security system and the use of individual and collective self-defence, see, DW Bowett, Self-Defence in International Law (F.A. Praeger, NY, 1958) 184–189.
See, Resolution 1267 of 15 October 1999 on the Taliban to enforce the Security Council’s demand to turn over Osama bin Laden and stop providing sanctuary to terrorists in Afghanistan. JE Stromseth, The Security Council’s Counter-Terrorism Role: Continuity and Innovation, An Imperial Security Council? Implementing Security Council Resolutions 1373 and 1390, 97 Am Society Intl L Proceedings (2003) 41.
For an analysis of the role of the Security Council in dealing with international terrorism in the context of its responsibility to maintain international peace and security, see, Ibid. 43.
For the text of the SC Resolution 1269 (19 October 1999), see <http://www.un.org/Docs/scres/1999/sc99.htm>.
See S.C. Res. 1390 (16 Jan 2002) at <http://www.un.org/Docs/scres/2002/sc2002.htm>.
S/RES/1377 (2001) recognized that many States will require assistance in implementing all the requirements of resolution 1373 (2001). It invited States to inform the Counter-Terrorism Committee of areas in which they require such support, enjoining the Counter-Terrorism Committee ‘to explore ways in which States can be assisted, and in particular to explore with international, regional and subregional organizations: the promotion of best-practice in the areas covered by resolution 1373 (2001), including the preparation of model laws as appropriate, the availability of existing technical, financial, regulatory, legislative or other assistance programmes which might facilitate the implementation of resolution 1373 (2001), the promotion of possible synergies between these assistance programmes.’ For the text of resolution 1368 (12 September 2001) <http://www.un.org/Docs/scres/2001/sc2001.htm>.
Resolution 1373 (28 September 2001) decided that all States shall:
(a) Prevent and suppress the financing of terrorist acts; (b) Criminalize the wilful provision or collection, by any means, directly or indirectly, of funds by their nationals or in their territories with the intention that the funds should be used, or in the knowledge that they are to be used, in order to carry out terrorist acts; (c) Freeze without delay funds and other financial assets or economic resources of persons who commit, or attempt to commit, terrorist acts or participate in or facilitate the commission of terrorist acts; of entities owned or controlled directly or indirectly by such persons; and of persons and entities acting on behalf of, or at the direction of such persons and entities, including funds derived or generated from property owned or controlled directly or indirectly by such persons and associated persons and entities; (d) Prohibit their nationals or any persons and entities within their territories from making any funds, financial assets or economic resources or financial or other related services available, directly or indirectly, for the benefit of persons who commit or attempt to commit or facilitate or participate in the commission of terrorist acts, of entities owned or controlled, directly or indirectly, by such persons and of persons and entities acting on behalf of or at the direction of such persons.
It also decided that all States shall:
(a) Refrain from providing any form of support, active or passive, to entities or persons involved in terrorist acts, including by suppressing recruitment of members of terrorist groups and eliminating the supply of weapons to terrorists; (b) Take the necessary steps to prevent the commission of terrorist acts, including by provision of early warning to other States by exchange of information; (c) Deny safe haven to those who finance, plan, support, or commit terrorist acts, or provide safe havens; (d) Prevent those who finance, plan, facilitate or commit terrorist acts from using their respective territories for those purposes against other States or their citizens; (e) Ensure that any person who participates in the financing, planning, preparation or perpetration of terrorist acts or in supporting terrorist acts is brought to justice and ensure that, in addition to any other measures against them, such terrorist acts are established as serious criminal offences in domestic laws and regulations and that the punishment duly reflects the seriousness of such terrorist acts;(f) Afford one another the greatest measure of assistance in connection with criminal investigations or criminal proceedings relating to the financing or support of terrorist acts, including assistance in obtaining evidence in their possession necessary for the proceedings; (g) Prevent the movement of terrorists or terrorist groups by effective border controls and controls on issuance of identity papers and travel documents, and through measures for preventing counterfeiting, forgery or fraudulent use of identity papers and travel documents.
See, E. Miller, The Use of Targeted Sanctions in the fight against International Terrorism—What about Human Rights? 97 ASIL Proceedings (2003) 46–51.
Thus the UN established three committees dealing with counter-terrorism related issues: Monitoring sanctions against Al-Qaida and the Taliban: The work of the 1267 Committee; Preventing proliferation of weapons of mass destruction: The work of the 1540 Committee; and Strengthening sanctions against terrorists and compensating victims: Establishing the 1566 Working Group. On the mandates of the three bodies, and information on13 international counter terrorism instruments or conventions adopted by the UNGA, see, <http://www.poa-iss.org/CASAUpload/Members/Documents/19@Background.pdf>.
See, of Resolution 1566 (2004) <http://www.un.org/ga/search/view_doc.asp?symbol=S/RES/1566%20(2004)> .
On the list and brief introduction to the 13 international anti-terrorism conventions see note 32 above.
On the work of the UN Committee on international terrorism and the lack of agreement on a comprehensive definition covering international terrorism, see PS Rao, International Terrorism, Self-Determination and National Liberation, in, RK Dixit & C Jayaraj (eds) Dynamics of International Law in the New Millennium (Indian Society of Intl L/Manak Publications, New Delhi, 2004) 115–144. The Indian view is that “Article 2 and 18(2)…are in conformity with the position of law governing armed struggles of different kind. …that legitimate causes must be pursued within the limits of international law and well-accepted standards of human rights and not outside its framework”, id., pp. 134–135.
Following terrorist attacks perpetrated by ISIL — also known as Da’esh — on 26 June in Sousse, on 10 October in Ankara, on 31 October over the Sinaï Peninsula, on 12 November in Beirut and on 13 November in Paris, among others, the Security Council adopted the Resolution by an unanimous vote. For the text of the resolution and in particular paragraph 5, and statements made at the time of adoption, see, <http://www.un.org/press/en/2015/sc12132.doc.htm>.
For an analysis of this resolution, and for the view that this Resolution, for all its ambiguities and limited geographical scope, given the fact that ISIL is not a State and its present operations extend beyond Iraq and Syria into Libya and Yemen and possibly into other countries as well, is a call for “sting operations” going beyond mere measures of “police action” to encompass genuine “military” action. Peter Hilpold, The fights against terrorism and SC Resolution 2249(2015): Towards a more Hobbesian or a more Kantian International Society, 55 Indian J Intl L (2015) 553. The author concluded that the Resolution is ‘neither to be seen as a resolution of pure authorization nor primarily as a document specifying the criteria for self-defence in a specific case.’ This resolution, according to Hilpold, ‘lies somewhere in between and addresses Chapter VII as a whole.’ As such, he submits that ‘States fighting ISIS are defending themselves but also the international community as a whole and for this they are called upon to act’.
For a succinct analysis of the role of CTC, see, Stromseth, supra note 26, 43–44. It is noted that its functions are evolving over a period in three stages: first, help States to establish counter-terrorism legislation and become party to the various international counter-terrorism conventions and protocols; second, ensure that States have effective and coordinated executive mechanism to implement all areas of Resolution 1373; and finally in the third stage, CTC will focus on State action to bring terrorists and their supporters to justice.
C. Gray, The Use of Force and the International Legal Order, in, MD Evans (ed) International Law (OUP, Oxford 2006) 589. See, T. Fracnk, Recourse to Force. State Action Against Threats and Armed Attacks (CUP, Cambridge, 2005).
On the true meaning and purpose of Jehad, see, M.K.Nawaz, The Doctrine of Jehad in Islamic Legal Theory and Practice, 8 Indian Yrbk Intl Aff (1959) 32–48. See, also, Majid Khadduri, Islam and Modern Law of Nations, 50 Am J Intl L (1956) 358–372.
For a latest reiteration of Pakistani support to and the claim of self-determination as a justification for armed activities and crimes being committed inside and against Indian state of Jammu and Kashmir see the statement of Khwawaja Asif, Defence Minister of Pakistan. While speaking in the Upper House of Parliament of Pakistan, Khwawaja Asif said, ‘Pakistan will continue political, diplomatic and moral support to the Kashmiris in their struggle for right of self-determination.’ See, Pakistan Senate deplores Modi for terrorism slur, Gulf Times (Doha, Qatar) 17 January 2017, 23.
The Nicaragua case, supra note 18, 109–110 . For an examination of the principle of self-determination and its non-applicability as justification for waging wars of liberation, PS Rao, International Terrorism, Self-Determination and National Liberation, in Dixit & Jayaraj, supra note 36, 115, 123–129, 144. It is also pointed out that ‘neither human rights, democracy, or self-determination are acceptable grounds for waging war, now for that matter are traditional just war causes or righting wrong …’. See, Oscar Schachter, International Law in Theory and Practice (M. Nijhoff, Boston, 1991) 128.
One of the prime examples of an organization engaged in international terrorism is Al-Qaeda. Islamic State of Iraq and al-Sham (ISIS) on the other hand is a case of group of Islamic fundamentalists engaged in civil war and taking advantage of the civil war in Syria occupying considerable stretch of Iraq and Syria and establishing a de facto Caliphate/State known as ISIL or Daesh. It is noted, ‘The danger is not limited to individuals attracted to ISIS flag. In November, Baghdadi demanded that all Islamist and jihadi movements across the world be dissolved or absorbed into his “caliphate”. Many groups have taken up the call, and new ones continue to do so. While some were previously unknown, others, including Boko Haram in Nigeria and Ansar Beit al-Maqdis in Egypt, have long been prominent actors in their own countries’ conflicts. Moreover, the appeal of the universal caliphate is fracturing established groups that have not declared allegiance. See, Peter Welby, What is ISIS?, Backgrounder (16 Nov 2015) <http://tonyblairfaithfoundation.org/religion-geopolitics/commentaries/backgrounder/what-isis?>. Since June 2014, when ISIL proclaimed itself to be the Islamic State, according to a running count kept by CNN, it has “conducted or inspired” over 70 terrorist attacks in 20 countries, not including Syria and Iraq.
Barring exceptions like the case of the Taliban and Al-Qaeda which engaged in international terrorism with Afghanistan as their base and later shifting to an area not under effective authority or control of Afghanistan and Pakistan. The case of Al Shabab, a militant group operating out of Somalia mostly targeting people and places in the neighboring Kenya comes close to be part of international terrorism. See, Charlie Savage, Eric Schmitt & Mark Mazzetti, Obama Expands War With Al Qaeda to Include Shabab in Somalia, The New York Times, (New York) 27 Nov 2016.
See, P S Rao, Countermeasures in International Law: The Contribution of the International Law Commission, in Studi Di Diritto Internazionale Onore di Gaetano Arangio-Ruiz, vol.II (Editoriale Scientifica, Napoli, 2004), 853–880.
In such a situation, it is suggested that right of self-defence could be claimed against a ‘territory that is somehow linked to but factually irrelevant to the actual attack.’ See, Comments of Schwebel, in, Roucounas Report, supra note 22, 168–232, 181.
D Thürer, The “Failed State” and International Law, 81 Intl Rev Red Cross (1999) 731,733–36.
See Resolution 1566 (2004) of 8 October 2004 noted above for a working definition on terrorism adopted by the UN. In his chapter on “international response to terrorism”, Cassese concludes that ‘we now have a generally acceptable definition of terrorism.’ Antonio Cassese, International Law (OUP, NY, 2005) 80.
See Article 2(4) of the UN Charter. For the comment that a policy of force cannot find a place in international relations, despite the many deficiencies of the contemporary world order to control and regulate unilateral or collective use of force to achieve preferred objectives, see, the Corfu Channel case  ICJ Rep 35.
See, commentary to Article 21 of the International Law Commission’s draft articles on State Responsibility. J. Crawford, International Law Commission’s draft articles on State Responsibility (CUP, Cambridge, 2002) 166.
Brownlie relies on the jurisprudence of the International Court of Justice and the work of the International Law Commission to highlight this point. See, Ian Brownlie, International Law at the Fiftieth Anniversary of the United Nations, 255 Recueil des Cours (1995) 203, 207, 209–210. B Roth, Bending the Law, Breaking it, or Developing it? The United States and the Humanitarian Use of Force in the Post-Cold War Era, in, M. Byers & G. Nolte (eds) The United States Hegemony and the Foundations of International Law (CUP, Cambridge, 2003) 232–263.
The conditions for the exercise of the right of self-defence are well settled: as the Court observed in its Advisory Opinion on Legality of the Threat or Use of Nuclear Weapons, (ICJ Reports 1996 (1), p. 245, para. 41) The submission of the exercise of the right of self-defence to the conditions of necessity and proportionality is a rule of customary international law.’;and in the case concerning Military and Paramilitary Activities in and against Nicaragua, the Court referred to a specific rule “whereby self-defence would warrant only measures which are proportional to the armed attack and necessary to respond to it” as “a rule well established in customary international law” (ICJ Reports 1986, p. 94, para. 176).
See the ICJ’s observation in the Oil Platforms case (Iran v. US) Judgment  ICJ Rep 161, 198 .
For a succinct but illuminating analysis of the Caroline incident, which prompted Daniel Webster to lay down conditions governing the right of self-defence claimed by the UK against US rebels opposing its rule in North America, see, Vaughan Lowe, International Law (Oxford Univ. Press, 2007) 275–276. Webster wrote that the British action of sinking the vessel operated by the rebels would be justified only if Britain could show ‘a necessity of self-defence, instant, overwhelming, leaving no choice of means, and no moment for deliberation’, and also that it did nothing unreasonable and excessive, since the act justified by the necessity of self-defence , must be limited by that necessity, and kept clearly within it’. Lowe adds, ‘While Britain and the United States differed over the question whether these criteria were met, they both accepted the essence of this definition of self-defence.’ Quoted in, Ibid.
See, Oil Platforms case, note 53, 196 .
Matheson however considers the test laid down by the Court and rejecting any “measure of discretion” in this regard as “unrealistic”. But it is possible to view the Court’s observation as not disallowing any benefit of doubt and action in the light of facts at the disposal of a State at the time it takes the action. Actions in exercise of “discretion” could be far more sweeping than the action taken in the light of facts known and judgments made in good faith. Hence the author does not consider that there is any contradiction between the observations of the Court and Matheson on the other hand. M.J. Matheson, International Civil Tribunals and Armed Conflicts (M. Nijhoff, Leiden/Boston, 2010) 267.
Oil Platforms case, supra note 53, 198 .
Quoted, in, Willam H. Taft, IV, Self-Defense and the Oil Platforms Decision, 29 Yale J Intl L (2004) 295–306, 305.
Ibid. For the view of Schachter, used as a basis for this conclusion, see, Schachter, supra note 43, 154.
The Court held that whether a “threat” is contrary to Article 2 (4) ‘depends upon whether the particular use of force envisaged would be directed against the territorial integrity or political independence of a State, or against the Purposes of the United Nations or whether, in the event that it were intended as a means of defence, it would necessarily violate the principles of necessity and proportionality’. See, Legality of Threat or Use of Nuclear Weapons,  ICJ Rep 246 . See, Wilmerhurst, Chatham House Principles, infra note 132, 967–968.
Separate opinion of Judge Simma, in, Armed Activities on the Territory of the Congo (Democratic Republic of the Congo v. Uganda), Judgment,  ICJ Rep 168, 335–336.
Matheson, supra note 56, 96–104.
Ibid . The ICJ did not find active negotiations as a bar for exercising its judicial function. Ibid. [106, 108].
Citing paragraph (1) of the commentary of the Commission to Article 50 of its draft Articles on the Law of Treaties, ILC Yrbk (1966-II) 247. See, Nicaragua case, supra note 18, 100 .
Nicaragua case, supra note 18, 14 .
Ibid. 101 .
Matheson, supra note 56, 251.
Ibid. 108 .
Ibid. 103 .
Ibid. 104 .
Ibid.  brackets added.
‘These were the first incidents of what later became known as the “Tanker War” : in the period between 1984 and 1988, a number of commercial vessels and warships of various nationalities, including neutral vessels, were attacked by aircraft, helicopters, missiles or warships, or struck mines in the waters of the Persian Gulf”. Ibid. 175 .
The ICJ noted:
The conditions for the exercise of the right of self-defence are well settled: as the Court observed in its Advisory Opinion on Legality of the Threat or Use of Nuclear Weapons, “The submission of the exercise of the right of self-defence to the conditions of necessity and proportionality is a rule of customary international law” (I. C. J. Reports 1996 (1), p. 245, para. 41); and in the case concerning Military and Paramilitary Activities in and against Nicaragua, the Court referred to a specific rule “whereby self-defence would warrant only measures which are proportional to the armed attack and necessary to respond to it” as “a rule well established in customary international law” (I. C. J. Reports 1986, p. 94, para. 176).
Ibid. 198 .
Applying the test of “necessity”, the ICJ held:
In the case both of the attack on the Sea Isle City and the mining of the USS Samuel B. Roberts, the Court is not satisfied that the attacks on the platforms were necessary to respond to these incidents. In this connection, the Court notes that there is no evidence that the United States complained to Iran of the military activities of the platforms, in the same way as it complained repeatedly of minelaying and attacks on neutral shipping, which does not suggest that the targeting of the platforms was seen as a necessary act. The Court would also observe that in the case of the attack of 19 October 1987, the United States forces attacked the R-4 platform as a “target of opportunity”, not one previously identified as an appropriate military target.
Ibid. . Applying the test of proportionality, the Court held that although it cannot assess the proportionality of the US use of force in the present case, in the absence of all other aspects of that operation before the Court, inter alia, the destruction of two Iranian frigates and a number of other naval vessels and aircraft. As a response to the mining, by an unidentified agency, of a single United States warship, which was severely damaged but not sunk, and without loss of life, neither “Operation Praying Mantis” as a whole, nor even that part of it that destroyed the Salman and Nasr platforms, can be regarded, in the circumstances of this case, as a proportionate use of force in self-defence. Ibid. 198–199.
Ibid. 194 . On the status of Israel as occupying Power, see, Ibid. 167 .
Ibid. 222–223 .
Ibid. 223 .
Nicaragua case, supra note 18, .
Congo case, supra note 61, 62–63 .
Judge Simma said:
As is well known, these developments were triggered by the terrorist attacks of September 11, in the wake of which claims that Article 51 also covers defensive measures against terrorist groups have been received far more favourably by the international community than other extensive re-readings of the relevant Charter provisions, particularly the “Bush doctrine” justifying the pre-emptive use of force. Security Council resolutions 1368 (2001) and 1373 (2001) cannot but be read as affirmations of the view that large-scale attacks by non-State actors can qualify as “armed attacks” within the within the meaning of Article 51.
Judge Simma, Ibid. 337 .
Ibid. 337 . For the views of Judge Burgenthal, similar to Judges Koojimans and Simma, see, Declaration, Legal Consequences of the Construction of a Wall in the Occupied Palestinian Territory, Advisory Opinion  ICJ Rep 136 . In this case the Court held that the inherent right of self-defense in article 51 was available in the case of an armed attack by one State against another State… The Court in this case was reluctant to accept the Israeli contention that the construction of the wall in the occupied territory of Palestine was in pursuance of its right of self-defense. The Court further noted that the acts Israel complained of, by its own account, were acts of non-State actors from inside the territory which was under its occupation, thus implying for the purpose of invocation of Article 51, attacks must originate from source situated outside the territory under the effective authority and control of the victim State. In the words of the Court, ‘Article 51 of the Charter thus recognizes the existence of an inherent right of self-defence in the case of armed attack by one State against another State. However, Israel does not claim that the attacks against it are imputable to a foreign State’. Ibid. 194 . On the status of Israel as occupying Power, see, ibid. 167 .
See, Ibid. 338 .
Cf. ILC Commentary to Art. 4, para. (1). Ibid., 203 .
Ibid., 204 .
Ibid., 205 .
Ibid. 295 .
Article 4,5, and 8 of Articles on Responsibility for internationally wrongful acts of a State, in the Report of the International Law Commission on the work of its fifty-third session (2001), UNG.A, O.R, Suppl., No. 10, A/56/10, 40–44 (for Art. 4 and 5 with commentaries) 47–49 (for Art. 8 with commentaries; and 48  for distinguishing the Tadic case of the ICTY from the Nicaragua case on the ground that in former case it was not responsibility of States but individual criminal responsibility and the applicable law is not responsibility but applicable rules of international humanitarian law.
Ibid. . The Court noted also that ‘notwithstanding the very important support given by the Respondent to the Republika Srpska, without which it could not have conduct[ed] its crucial or most significant military and paramilitary activities’ (I.C.J. Reports 1986, p. 63, para. 111), did this signify a total dependence of the Republika Srpska upon the Respondent’. Ibid. 204 .
IT-94-1-A, Judgment, 15 July 1999.
Application of the Convention on the Prevention and Punishment of the Crime of Genocide (Bosnia and Herzegovina v. Serbia and Montenegro, supra note 95, 210 .
Ibid. 210 .
For a succinct summary of differing views on the matter, see Matheson, supra note 56, 253–273. For various comments, see, Roucounas Report, supra note 22, 92–93[29–30].
Taft relies on the views of Brownlie and Higgins in this regard at pages 301–302, fn. 38. Taft, supra note 58, 295–306.
See for a discussion on this matter of distinction between mere ‘frontier incidents’ and grave forms of attack for the purpose of triggering right of self-defence under Article of 51, Jan Kittrich, The Right of Individual Self-Defense in Public International Law (Logos Verlag Berlin GmbH, 2008), pp. 77–72 citing the Ethiopia-Eritrean Commission (PCA, 2005) which rejected the claim of Eritrea that the frontier incidents involved constituted a basis for its exercise of right of self-defence as provided under Article 51.
See Comment of Reisman in Deliberations on the Roucounas Report, supra note 22, 184.
Matheson, Ibid. 253 (for the views of Judge Greenwood).
The views of Judge Jennings, as part of his dissent in the Nicargagua case, are pertinent and highly persuasive. He pointed out that while ‘mere provision of arms cannot be said to amount to an armed attack’, the provision of arms, coupled with other kinds of involvement nevertheless, be a very important element in what might be thought to amount to armed attack’. Accordingly, to him, to say that the provision of arms, coupled with “logistical or other support” is not armed attack is going much too far. ‘Logistical support may itself be crucial.’ Further, he opposed any restrictive interpretation of the term “armed attack”. First he referred to the contemporary conditions: Such an approach, in his view, would ‘be neither realistic nor just in the world where power struggles are in every continent carried on by destabilization, interference in civil strife, comfort, aid and encouragement to rebels, and the like’. Second, he emphasized that ‘The original scheme of the United Nations Charter whereby force would be deployed by the United Nations itself, in accordance with the provisions of Chapter VII of the Charter, has never come into effect. Therefore an essential element in the Charter design is totally missing. In this situation it seems dangerous to define unnecessarily strictly the conditions for lawful self-defence, so as to leave a large area where both a forcible response to force is forbidden, and yet the United Nations employment of force, which was intended to fill that gap, is absent.’ See, Nicaragua case, supra note 18, fn. 52. In his separate opinion, Judge Kooijmans also pointed out that ‘the almost complete absence of governmental authority in the whole or part of the territory of certain States has unfortunately become a phenomenon as familiar as international terrorism’. See separate opinion of Judge Kooijmans in the Congo case, supra note 61 . Judge Simma was in full agreement with his conclusion, Congo case, supra note 61.
See, Rosalyn Higgins, Problems and Progress: International Law and How We Use It (1994) 251. Dinstein, infra note 148, 176. See, JL Hargrove, The Nicaragua Judgment and the Future of the Law of Force and Self-Defense, 81 American J Intl L (1987) 139.
Matheson suggested that the ‘basic requirement for collective response should be the same for individual response: if proportionate force is genuinely necessary on a collective basis to deal with an unlawful use of force, international law should not prohibit it’. See, supra note 56, 264. For the views of Judges Jennings and Schwebel, opposing any formal requirement for the right of collective response to arise, see, supra note 56, 263, fn 41.
‘In Nicaragua, the ICJ identified two factors from which “complete dependence” may be inferred. The fact that the outside power conceived, created and organized the secessionist entity, or the armed opposition group that established the secessionist entity, seems to establish a strong presumption that the secessionist entity—as its creature—is completely dependent on the outside power and is nothing more than its instrument or agent.’ For a very thorough discussion of the concepts of “control” relevant for attribution of responsibility to a State for acts of non-State actors, see, S Talmon, The Responsibility of Outside Powers for acts of Secessionist Entities, 58 Intl & Comp L. Q. (2009) 493–517, 499, fn. 36 (for citations).
The “degree of dependence” of non-State actors on the State in question determines the type of control the latter is deemed to have over the former. “Control” would be “strict” if the “degree of dependence” of non-State actors on the State is complete as opposed to “effective control”, where the “degree of dependence” is partial and limited to particular act or acts of terrorism. In other words, the State must be shown to have “strict control” over the non-State actors indulging in terrorist acts to treat them as agents or organ of the State on whom they are completely dependent. This requires evidence to show that not only the degree of dependence is complete and that it extended to all fields but the State in question actually exercised that high degree of control over the non-State actors in the performance of the wrongful acts.
Control could be termed as “overall” if the test consisting of two parts could be met: (a) The provision of financial and training assistance, military equipment and operational support; (b) Participation in the organisation, coordination or planning of military operations. Prosecutor v Kordić & Čerkez (Judgment) ICTY-95-14/2-T (26 Feb 2001) , and (Judgment) ICTY-95-14/2-A (17 Dec 2004) . Also see, Prosecutor v Naletilic and Martinovic (Judgment) ICTY-98-34-T (31 Mar 2003) . Further, the “overall control” test could be deemed to be applicable only if one goes by the ICTY Appeals Chamber, which appeared to reject on this point the test of “effective control” enunciated by the ICJ in the Nicaragua case, holding that it is not persuasive in the case of organized groups. This conclusion was further sought to be justified on the ground that ‘the situation of an organized group was different from that of private individuals’. Talmon, supra note 118, 505. The “overall control” test can be fulfilled, even if the secessionist entity has autonomous choices of means and tactics while participating in a common strategy with the State in question, even if it did not have actual control over the particular act, which is necessary for the test of effective control to be established. In that sense the “overall control” test is less strict than the “effective control” test.
Noting that the Court in the Bosnia v. Serbia case applied the test of ‘effective control … to a situation different from that presented in the Nicaragua case’, Judge Al-Khasawneh pointed out that in ‘the present case, there was a unity of goals, unity of ethnicity and a common ideology, such that effective control over non-State actors would not be necessary.’ See, Application of Genocide Convention, supra note 95, 255 . In his view, ‘a strong case can be made for the proposition that the test of control is a variable one. It would be recalled that some ILC members drew attention to the fact of there being varying degrees of sufficient control required in specific legal contexts’. Judge Al-Khasawneh, Ibid. 255 .
Judge Al-Khasawneh, ibid, 256 .
Trapp, supra note 5, 156 (italics added).
On the importance of threshold, see Draft principles on the allocation of loss in the case of transboundary harm arising out of hazardous activities, with commentaries (United Nations, 2006), (A/61/10), Commentary to Article 2, paras 1–3, pp. 122–124. See also Draft articles on Prevention of Transboundary Harm from Hazardous Activities, with commentaries (united Nations, 2001), (A/56/10), paras 1–7 of the Commentary to article 2, pp. 152–153. As noted in para 15 at p. 94 of the Commentary to article 3 of the Draft articles and commentaries thereto adopted by the Drafting Committee on second reading: articles 1–33, reproduced in Yearbook…1994, vol. II (Part Two), para. 222,…, “adverse effect upon third watercourse States… must be capable of being established by objective evidence and not be trivial in nature”.
See, Present Problems of the Use of Armed Force in International Law: A. Self-defence, Resolution 10A, 27 Oct. 200 Resolution of the Institut de Droit Interantional, Session de Santiago, 2007, Commission 10: <http://www.justitiaetpace.org/idiE/resolutionsE/2007_san_02_en.pdf>.
‘[S]elf-defence is presented as a normative flux that oscillates between what were called “minimalist” (for strict application) and “realist/neorealist” (leading to an altogether denial of the usefulness of Article 51) positions, from those who find Article 51 sufficient to cover the actual needs of the international community, to those pretending that the provision is largely incoherent or even that it does not express current international law.’ See, the Roucounas Report, supra note 22, 81 .
"In larger freedom: towards development, security and human rights for all”, UNGA doc. A/59/2005. “Imminent threats are fully covered by Article 51…”. See, the Report of the UN Secretary General, 33 . Dinstein objected to the concept that imminence of threat should be “manifest” for giving rise to the right of self-defence. ‘As the author of the term, he would therefore like to point out that interceptive self-defence usually came about in response to an embryonic armed attack which was, by definition, not manifest at all.’ See, Deliberations on the Roucounas Report, supra note 22, 177. Tomuschat however took an opposite view. According to him, accepting right of self-defence against embryonic armed attack, as suggested by Dinstein “goes too far”; and accepting that approach would amount to “effectively” endorsing ‘the doctrine of preventive self-defence as expressed by the USA.’ He, however, supported the idea of “interceptive” self-defence where the attack was not “imminent” but already in preparation, “interceptive” should not be interpreted as “embryonic”, Deliberations on the Roucounas Report, Ibid. 183. Lowe appear to endorse the view of Tomuschat when he suggested that the ‘right of self-defence cannot require a State to await an actual attack before lifting a finger to defend itself—though it certainly requires the most serious efforts to avert the use of force’. As an illustration of imminent attack meriting an anticipatory self-defence, reference was made to the right of self-defence claimed by Israel in the Six-Day war against its Arab neighbors, when preparations for an attack reached an advanced stage. See, Lowe, supra note 54, 276.
It is concluded ‘it can be said that the doctrine of pre-emption encompasses unilateral as well as collective reactions against new types of threats. In the same time it widens the concept of threat, eliminates the requirement of imminence and goes far beyond Article 51 and customary law, with or without reference to the Caroline formula … It is also argued that under present international law there is no need for the concept of pre-emptive self-defence. ‘It is clearly incompatible with present Charter law and does not fall within the narrow frame of the concept of anticipatory self-defence’. It adds confusion in an already controversial area and has been qualified “unnecessary and divisive”,’ Roucounas Report, supra note 22, 126 .
For a comprehensive analysis of different types of situations in which claim of exercise of right of self-defence is or may be lawful, see, Roucounas Report, Ibid. 116–126 [82–102]. There are ‘at least four doctrines on the question of the triggering of the right of self-defence in response to an armed attack: the first is classic, “if the attack actually occurs”; the second adds ‘once the attack has been launched but did not yet reach the territory of the victim State’, the third justifies self-defence ‘also if the threat of an attack is imminent’, and the relatively more recent one alleges that the right of self-defence can further be exercised ‘if the attack is supposed to occur’. Ibid. 117 . On the ‘manifestly imminent attack (objectively verified)’, the Roucounas Report noted that ‘the general stand is to accept a Charter (or a Charter in parallel with customary law) right to a strictly limited, that could be qualified stricto sensu, anticipatory self-defence, as this can be useful for the preservation of the whole system of the Charter.’ Examples given by the doctrine are: ‘A missile that is already launched or the navy that moves in combat formation towards the territory of the target State …’. Ibid. 118 .
This terse statement is otherwise an endorsement of what is considered a majority opinion on the basis of contemporary practice. It is first noted that ‘The question of threat invoked by drafters of the Charter during the discussion on self-defence was not retained’, suggesting that the fact that two World Wars (August 1914, September 1939 and May 1940) begun with the aggressor invoking imminent threat and self-defence played a role in that decision. Secondly, it is pointed out ‘The dangers of abusive appreciation of threat are recognized by all, both by those in favor, and those against a broader interpretation of Article 51.’ Finally, the contemporary trends in decision as summarized by Franck were cited as a basis for this conclusion: ‘These provisions (on collective measures taken by the Security Council) permit the use of force against many kinds of “threats to the peace” that do not take the form of an actual armed attack. Such action, however, must first be authorized by the Security Council, as it was in response to such threats of the peace as the military coup in Haiti, the disintegration of civil governance in Somalia, and the humanitarian crises in the former Yugoslavia, Albania, and Rwanda. In each instance, the decision to authorize the resort to force was made collectively.’ See, Ibid. 110–112 [66–70]. See, also UN SG Report, In Larger Freedom, Ibid. 102, where it is noted that ‘The task is not to find alternatives to the Security Council as a source of authority but to make it work better’. Ibid. 33 .
For the full text of the Principles, see, E Wilmhurst, The Chatham House Principles of International Law on the Use of Force in Self-Defence, 55 Intl & Comp L Q (2006) 963–972. ‘The Principles are intended to provide a single source of expert interpretation of the rules of self-defence’; without being fully self-explanatory as to the choices, giving ‘brevity …precedence over explanation” and without engaging the responsibility of any of members of the Group who participated in their preparation. Wilmhurst, Ibid. 963. On “imminent attack” and its relationship to principles of necessity and proportionality, see, ibid. 967–969. In this connection, it is noted that the ‘level of force used is not greater than that necessary to end the attack or remove the threat.’ Further, while the force is used should not aim to “punish” an aggressor, it is suggested that force used ‘must take into account the self-defence operation as a whole.’
It is emphasized that ‘State practice in this field, including the recent practice of the Security Council, gives no support to the restriction of self-defence to action against armed attacks imputable to a State; indeed there is state practice the other way.’ Ibid. 970.
The Leiden Policy Recommendations on Counter-terrorism and International Law (1 April 2010) <http://www.parlementairemonitor.nl/9353000/1/j4nvgs5kjg27kof_j9vvij5epmj1ey0/vify7910urzk/f=/blg68451.pdf>.
All efforts should be made to exhaust means other than force to prevent and repress terrorist activities. States and the Security Council should give priority, wherever possible, to law enforcement measures and recognise that the use of force is a measure of last resort, to be employed only where absolutely necessary”. On law enforcement measures and the need for improved international judicial and intelligence cooperation among States, see, Ibid. 9–10 . It is stressed inter alia that States should ‘criminalize the terrorist acts defined by relevant multilateral and regional treaties’ (mentions about 16 UN instruments in this regard); recommends framing international cooperation in respect of mutual legal assistance , as distinct from the policy and practice applicable to extradition, eliminating ‘barriers created by dual criminality, transnational recognition of search warrants, and wider recognition of asset freezing and confiscation orders’, to promote timely and flexible mutual legal assistance; and urging States to ‘increase their ability to interdict the flow of terrorist financing, and in particular should expand the processes available for non-conviction based forfeitures of assets under judicial oversight’. Ibid. 11 .
Ibid. 12 .
Requirement of necessity would be justified under these recommendations if “States relying on self-defence” could ‘show that the territorial state’s action is not effective in countering the terrorist threat. Whether this is the case depends on circumstances such as the nature and gravity of the threat, including the territorial state’s attitude vis-à-vis the group operating on its territory.’ This formulation broadly captures the same sense as the Chatham House Principles.
Ibid. 17–25 (part III). It deals with several areas central to both the legal regimes.
D. Bethlehem, Self-Defence Against an Imminent or Actual Armed Attack by Non State Actors, 106 American J Intl L (2012) 769–777.
‘At the core of Bethlehem’s thesis is a conflation of jus ad bellum and jus I bello and some questionable interpretations of both.’ G Rona & R Wala, No Thank You to a Radical Rewrite of the Jus Ad Bellum, 107 American J Intl L (2013) 386.
O’Connel concludes with a warning from Louis Henkin: ‘Extending the meaning of “armed attack” and “self-defense”, multiplying exceptions to the prohibition on the use of force and the occasions that would ;permit military intervention, would undermine the law of the Charter and the international order established in the wake of world war.’ Mary Ellen O’Connel, Dangerous Departures, 107 American J Intl L (2013) 380–386, fn.29. Professor Henkin, O’Connel said, was responding to proposals made by Jean Kilpatrick & Allan Gerson in the context of the dialogue on the Regan Doctrine, Human Rights, and International Law. See, Henkin, The Use of Force: Law and Policy, in, L Henkin et al (eds) Right v. Might: International Law and the Use of Force, 2nd edn (Council on Foreign Relations , NY,1991).
Matheson, supra note 56, 275.
The concept that use of force should be “large scale” for right of self-defence to arise is broadly accepted only in so for as it distinguishes the same from mere frontier incidents. However, there is influential view that quality of the use of force may be a factor only for determining whether the test of proportionality is met or not; and that it is not relevant for the lawful invocation of the right of self-defence. See Rosalyn Higgins, Problems and Progress: International Law and How We Use It (OUP, Oxford, 1994) 251. Yoram Dinstein, War, aggression, and Self-Defence, 3rd end (CUP, Cambridge, 2001) 176; JL Hargrove, The Nicaragua Judgment and the Future of the Law of Force and Self-Defense, 81 Am J Intl L (1987) 139. See generally, Comment of Reisman, in, Roucounas report, supra note 22.
It may be recalled that the Court in the Oil Platforms case did not ‘exclude the possibility that the mining of a single military vessel might be sufficient to bring into play the “inherent right of self-defence”, supra note 53, 20 (fn.68). For the views of Judge Jennings, see, supra note 97. In his separate opinion, Judge Kooijmans also pointed out that ‘the almost complete absence of governmental authority in the whole or part of the territory of certain States has unfortunately become a phenomenon as familiar as international terrorism’. See separate opinion of Judge Kooijmans in the Congo Case, supra note 61, . Judge Simma was in full agreement with his conclusion, Ibid. note 80 above. See also comments of Professor Roucounas, Rapporteur of the IDI, supra note 22, 190, where he approvingly notes these concerns and observed that there are “different degrees of gravity”.
Declaration on Principles of International Law concerning Friendly Relations and Cooperation among States in accordance with the Charter of the United Nations, A/RES/2625.
(XXV) of 24 Oct 1970, Principle 1, para 9 equates organizing, instigating, assisting or participating in acts of civil strife in another State with the use of force when such acts themselves involve a threat or use of force. Similarly, Article 3(g) of the UN General Assembly’s Declaration on the Definition of Aggression, which is reflective of customary international law, provides that the “substantial involvement” of a State in acts of armed force carried out by armed groups in another State constitutes an act of aggression which is considered to be ‘the most serious and dangerous form of the illegal use of force’. See Declaration on the Definition of Aggression, A/RES/3314 (XXIX) of 14 Dec 1974, preamble, para 5. For the customary international law status of Art 3(g) of the Definition, see Nicaragua (n 22) para 195; Armed Activities (n 6) para 146.
Special Rapporteur Roucounas responded to a query from Feliciano during the consideration of the Resolution on self-defence by the Institute at its 2007 Santiago Session ‘that the State’s objectives must be correlative to the force being stopped or repelled. Force in self-defence should not be used at random, but rather the State should target the illegal act being repelled’. See Deliberations on the Roucounas Report, supra note 22, 191.
As Lowe aptly points out ‘The concern is not simply that it might be used as an excuse for specific uses of force that are shown in retrospect not to have been justified, but rather that the assertion of the right to take pre-emptive action is in effect an assertion of a permanent right to intervene with force in third States by the handful of States that have the technology and equipment to enable them to do so’; and ‘it is feared as a manifesto for vigilante violence’. Lowe, supra note 54, 277.
Article 51 mandates this. Further, it is a good policy to enhance and not undermine the UN Charter system and the rule of law in a multilateral context. Koroma makes the point: ‘That is, that self-defence should be exercised collectively through the Security Council and General Assembly rather than unilaterally. Wherever a State acts in self-defence, this should be reported to the Security Council. If the Security Council goes on to mandate or authorise force then whatever is done must remain within the framework it sets out. There should also be monitoring to verify that a mandate is not exceeded’. Roucounas Report, supra note 22, 173–174.
Member, Advisory Board of the Indian J Intl L; President (2015–17) and Member (2005), Institut De Droit International; Judge Ad Hoc of the International Court of Justice (2004–2008); Arbitrator, Permanent Court of Arbitration (2010–2014); Member (1987–2006) and Chairman (2006) of International Law Commission, United Nations (1995); Special Rapporteur on International Liability topic (1997–2006); Former Legal Adviser of the Ministry of External Affairs of the Government of India (1985–2002).
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Rao, P.S. Non-state actors and self-defence: a relook at the UN Charter Article 51. Indian Journal of International Law 56, 127–171 (2016). https://doi.org/10.1007/s40901-017-0049-4
- Use of force
- Non-state actors
- Armed attack
- State responsibility