The legality of the United States intervention in Afghanistan: a public international law essay

by Sulman Hassan, graduate in law from Liverpool John Moores University

Sulman Hassan assesses the validity of the US contention that the Article 51 ‘right to self-defence’ is applicable in response to the September 11 atrocities in the light of the modern rules of International law. He considers the modern rule on the use of force, the applicability of UN Article 51, Role of the Security Council and the regional bodies, customary law requirements and the question of state responsibility. He concludes that the US has failed to satisfy, and instead violated the modern rules of International Law regarding the right to self-defence and instead relied on an ‘expansive’ interpretation
given by a limited number of academics.

The validity of the US contention that the Article 51 ‘right to self-defence’ is applicable in response to the September 11 atrocities needs to be assessed in light of the modern rules of International law.  The US contention needs to be considered along with the principle of jus cogens, the obligation not to use force, which is enshrined in Article 2 (4).  In order to critically assess the validity of the US contention, one must also consider the modern rules of International law which provide exceptions to Article 2 (4) [1] on the use of force.  Legal issues that need to be considered include:

• First, whether the US action is justified under Article 51, both the precise scope and interpretation of Article 51 need be determined.

• Secondly, the role of the Security Council and NATO [2] in light of US evidence presented, needs to be examined.

• Thirdly, was the US and UK bombing campaign within customary international law requirements established under the Caroline Case [3] .

• Fourthly, the issue of state responsibility needs to be considered, in particular whether the state of Afghanistan is responsible for actions taken by Al Qaeda [4] .

• Fifthly, it is important to consider recent US practice and an analysis from a US perspective.

• Finally it is necessary to contemplate whether current international law is still adequate in governing the use of force and also whether the US self-defence justification is valid under modern day International law.

Modern rules on the use of force

An appropriate starting point is a brief explanation of the modern rules on the use of force.  Use of force is condemned and has the status of jus cogens, a primary obligation for states not to go to use force [5] .  In modern day international law the principle is enshrined in Article 2 (4) [6] .  Article 2 (4) stipulates a general prohibition of the unilateral use of force [7] . In addition to the Article 2 (4), the International Court of Justice (ICJ) has clarified that a general ban on the use of force exists even in customary law running parallel to the charter [8] . However as mentioned there remain three exceptions to Article 2 (4): Article 51, the Charter right to self defence [9] ; action authorised by the Security Council; [10] and action by regional bodies with security council authorisation [11] .

Before addressing the legal issues on self-defence it is useful briefly to explain that there is lack of evidence made public linking Al Qaeda or the Afghan Government to the September 11 atrocities.  If the US had such ‘clear and compelling evidence’, as it claims [12] , then it should have been properly disclosed to the Security Council.  The US claims that disclosure would have amounted to the revelation of sensitive information.  On the other hand if one takes Charney’s view, disclosure of evidence should be required even if the state claims that classified information is disclosed [13] .  In brief Charney’s view seems more satisfying and that failure of the US to disclose credible evidence has thus not convinced the International Community.

The applicability of Article 51 to the US argument

Now that the modern rules on use of force are outlined and the fact there is insufficient disclosed evidence explained, it is useful to consider the applicability of Article 51 to the US argument.  Article 51 stipulates nothing ‘shall impair the inherent right of individual or collective self defence if an armed attack occurs against a member of the United Nations’ [14] . Whether the US action is justified under Article 51 depends on how Article 51 is interpreted.  A restrictive interpretation is that the UN Charter has displaced pre 1945 customary law on the issue of self-defence, while a permissive interpretation provides that pre 1945 customary law goes beyond rights guaranteed by the UN Charter [15] and thus even if Article 51 is not satisfied, use of force may be justified.

Using a restrictive interpretation it is difficult to see how Article 51 applies in relation to the September 11 atrocities.  Article 51 gives a state the right to repel an attack that is ongoing or imminent as a temporary measure until the UN Security Council can take steps necessary for international peace and security [16] . So on a restrictive view the right of self-defence does not include the right to retaliate once an attack has stopped [17] .

In order to trigger Article 51 it is necessary that there be an ‘armed attack’ within the meaning of the Charter.  The definition of ‘armed attack’ is broad, as established in the Nicaragua case [18] , where the ICJ held that the concept covers ‘the sending by or on behalf of a state of armed bands, groups, irregulars or mercenaries’ and a state’s ‘substantial involvement therein’ [19] .  So could the attacks on the US by Al Qaeda satisfy the Nicaragua definition of ‘armed attack?’ [20]

While the terrorist attacks on September 11 appear to be clearly within the definition of ‘armed attack’ committed by ‘armed bands’ [21] , it is difficult to see how action by the Al Qaeda terrorist group links the state of Afghanistan [22] . The ICJ [23] famously rejected the notion that mere assistance to rebels was an ‘armed attack’.  Applying the ICJ interpretation of ‘armed attack’ it appears improbable that that the Afghan Government sent Al Qaeda to the US with a view to commit terrorist acts as no disclosed evidence clarifies this. It is therefore logical to suggest that the US was not a victim of ‘armed attack’ within the meaning of Article 51 and the US use of force is contrary to Article 2 (4).  However, it is stressed that the US does not recognise the jurisdiction of the ICJ [24] and therefore from a US perspective any statements by the ICJ will be persuasive rather than authoritative.

Role of the Security Council and the regional bodies

Now that Article 51 has been addressed it is appropriate to move on to the role of the Security Council and the role of regional bodies.  In considering the role of the Security Council, it is a requirement [25] that any measures taken in self-defence ‘shall be immediately reported to the Security Council’ and then the Security Council will take ‘measures necessary to maintain international peace and security’.  There is no doubt the US did report its action [26] and in response the Security Council passed two resolutions condemning the September 11 attacks and announced a number of measures to fight terrorism [27] .  Furthermore, Resolution 1368 on the US claim of self-defence, recognised in its preamble the inherent right of individual or collective self-defence in accordance with the Charter, but the operative part of the resolution described the attacks as ‘terrorist attacks’ and not ‘armed attacks’. Thus neither resolution authorised the use of force and instead attempted to maintain peace and security by diplomatic means.  This means that US use of force is in violation of the UN Charter.

As regards the role of regional bodies, which in this case means NATO, to which the US is party, there is an obligation to act in accordance with the Charter [28] .   Invoking Article 5 of the Washington Treaty (as NATO did in response to the September 11 atrocities [29] ), that an attack on the US is an attack on all NATO members, is not authority for use of force as the NATO Treaty is subservient to the UN Charter [30] .  Therefore any NATO justifications for use of force are not authority unless it has Security Council backing.

Customary law requirements

Now it needs to be considered whether the US action was met by the customary law requirements established under the Caroline Case. It is well established that to be a valid use of force in terms of self-defence under international customary law [31] , there is a need that it be immediate, proportionate and necessary [32] .

In terms of immediacy, Boyle [33] suggests that only ‘on-the-spot’ responses to a terrorist armed attack are permissible [34] .  Boyle rejects post facto self-defence measure’s because in Boyle’s view an expansive reading of the self-defence doctrine to include retaliation and reprisal would provide states with justification for use of force. A denial of armed reprisal is consistent with prevailing scholarly opinion that reprisals are per se illegal [35] .  On this view it appears that US action should have been immediate for it to be legitimate under customary law as established in the Caroline case. However, US state practice suggests that a reasonable delayed response is acceptable [36] , where there is a need to gather evidence of the attacker identity to strike back in a targeted manner [37] .

On the issue of necessity, the test is that there be “a necessity of self defence, instant, overwhelming, leaving no choice of means, and no moment for deliberation” [38] .  US diplomatic means with the Taliban proved to be ineffective, as the Taliban refused to comply with US authorities [39] .  In reality necessity in relation to the September 11 atrocities seems to have, long since passed [40] before the bombing of Afghanistan [41] .  A claim of self defence would therefore only relate to future, anticipated attacks by Al Qaeda, hence Negroponte’s [42] reference to an ‘ongoing threat’. Legality of anticipatory self-defence is controversial in International law [43] .

Academic arguments have rejected the standard of necessity set in The Caroline Case, for instance, Coll [44] emphasises that the Caroline test exaggerates necessity in a time when war was a permissible option for states that had actually been attacked. [45] . If one is to accept Coll’s view it appears that the US need not satisfy the customary law requirement of necessity in order to act in self-defence.  However it is stressed that Coll’s view is just academic with no opinio juris and therefore not as authoritative as the customary standard under The Caroline case.

Whether the US action was proportionate to the September 11 atrocities is also questionable against the argument that the Taliban did not represent a direct threat to the US.  It was agreed in The Caroline case that a State exercising the right to self-defence must not do anything ‘unreasonable or excessive’.  However, jurists have advanced different interpretations of proportionality.  On a ‘deterrent’ approach Coll explains that self-defence measures ‘should be the minimum necessary to persuade him not to undertake aggression in the future’ [46] .  Schachter [47] extends the point by saying that in order to be a reasonable relation of means to ends, it is not disproportionate if in some cases the retaliatory force exceeds the original attack in order to serve a deterrent aim. Thus on this reasoning US action may be seen as proportional as there is a deterrent aim to prevent future ‘terrorist’ attacks. In sharp contrast to the deterrent approach is ‘tit for tat’ proportionality [48] which according to Intoccia is ‘any response to an act of aggression which employs a level of violence which is greater than is necessary to counter any continuing immediate threat must be viewed as impermissible’ [49] .  Thus the US action would not be permissible if one was to rely on Intoccia’s view as bombing the whole of Afghanistan would not be justified. In contrast to both of the above approaches is ‘cumulative proportionality’. [50] According to this approach an accumulation of small events, such as minor terrorist attacks, can justify a single longer retaliatory response in certain instances’ [51] .  This approach would suit previous US claims that Al Qaeda has been responsible for a number of terrorist attacks against the US [52] thus justifying US use of force.

In addition to the above some have argued that, although the September 11 atrocities are serious, a full-scale invasion of Afghanistan cannot be considered a proportionate response [53] . This means the objective of replacing the Taliban regime was in itself is probably not proportionate and of dubious legality [54] . No international legal instrument permits intervention to maintain or impose a democratic form of government in another state [55] .  Perhaps US actions find resonance if one applies Reisman’s [56] suggestion that a contextual interpretation of Article 2 (4) should be undertaken in light of the failings of the collective security system envisaged under the UN Charter [57] .  Applying Reismans standards, the US intervention might be considered permissible [58] since it removed the oppressive Taliban regime from Afghanistan.  However, a utilisation of an expansive interpretation of Art 2 (4) to ‘topple a repressive regime’ [59] is clear violation of the plain language of the Charter [60] . Further, Military Support given to the Northern Alliance by the US can only be justified if it is the Afghan Government who had committed an armed attack against the US.  Otherwise the US arming and support for the Northern Alliance is as illegal as its arming and support for the Contras was back in the 1980s [61] .

In summary, the customary law requirements of immediacy, necessity and proportionality appear not to have been satisfied. Maybe the US sees itself as having leeway in respect to proportionality and necessity to its initial reaction to the September 11 atrocities because of the gravity of the attack and the flexibility of the norms in the Charter regarding self-defence [62] .

State Responsibility

The issue of state responsibility regarding the US claim that Afghanistan was ‘harbouring’ Al Qaeda terrorists need to be considered. The US claim is questionable and if one applies the Nicaragua case, it would appear no state responsibility can be imputed to Afghanistan [63] as there is no disclosed evidence of Afghanistan issuing ‘specific instructions’ to Al Qaeda to carry out atrocities in the US.

Similarly if one applies the judgements of the International Criminal Tribunal for the former Yugoslavia (ICTY) in Prosecutor v Tadic 1999 [64] , to imply state responsibility the state accused needs to exercise ‘overall control’. The Taliban did not exercise  ‘overall control’ of Al Qaeda and therefore on the reasoning of the ICTY are not responsible for the actions of Al Qaeda.

In addition is the view of the International Law Commission (ILC), in its draft articles on State Responsibility of States for Internationally Wrongful Acts of 2001 [65] , which regards a state as responsible only:

… ‘if the … group of persons is in fact acting on the instructions of, or under the direction or control of, that state in carrying out the conduct’; if the … group of persons is in fact exercising elements of the governmental authority in the absence or default of the official authorities’; and ‘if and to the extent that the State acknowledges and adopts the conduct in question as its own’’… [66]

Applying the ILC recommendations, as there is no evidence to suggest that Al Qaeda was under specific instructions of the Afghan Government, it is unlikely that an Al Qaeda member holds authority in the Afghan government and it is unlikely that the Afghan government acknowledged such conduct as their own law, it is therefore reasonable to suggest that state responsibility can not be imputed to Afghanistan based on the reasoning of the ILC

However the US claim of state responsiblity may be merited by some academic opinion.  For example, Baker’s rendition of state responsibility is that even a ‘states toleration’ of terrorism can engender a victim’s right of response to an armed attack [67] .   Like Baker, Judge Soafer [68] , contends that state ‘sponsorship’, ‘support’, or ‘toleration’ can engender a victim state’s right to forcible response.  On this line of reasoning if ‘toleration’ was to equate to the US ‘harbouring’ claim there is academic support of the US ‘harbouring’ theory.  However if ‘harbouring’ is taken to mean ‘mere sanctuary’ then according to Cassese the law is ‘not entirely clear’ [69] .

Summing up on state responsibility it appears that the US position of self-defence is invalid as  the US ‘harbouring’ theory fails to satisfy any of the tests put forward by the ICJ, the ICTY, or the ILC.  Any support for the US ‘harbouring’ theory on state responsibility comes from limited academic opinion, which it must be remembered should be seen as persuasive rather than authoritative.

Conclusion

With little compliance to modern rules of International Law, the US appears to have relied on US and Israeli past practice.  US state practice seems to support the hypothesis that an ‘armed attack’ by a non-state group is sufficient to justify use of force under Article 51 [70] . From a US perspective Al Qaeda leadership cannot be seen as purely as a ‘non – state’ entity as it is said there is a symbiotic relationship between the two and the fact the Afghan government seems to tolerate the presence of Al Qaeda [71] .

In the past both the US and Israel have claimed self-defence for use of force in response to ‘terrorist attacks.  Their justifications include; self defence; the protection of nationals abroad; and deterrence.  Israel’s attack on Tunis in 1985 was widely condemned and seen as a violation of the UN Charter, but Israel claimed it targeted the PLO [72] headquarters in response to the protection of Israeli nationals abroad.  As for the US attack on Tripoli in 1986, the US argument to the UN Security Council was that the action was self-defence under Article 51 as it was intended to protect nationals abroad and to deter future terrorist attacks.  Furthermore, the US claimed to have acted in self-defence in response to embassy bombings in Kenya and Tanzania in 1998 by striking at targets in Sudan and Afghanistan.  It can thus be seen that US and Israeli action can be seen as pre-emptive and retaliatory amounting to reprisals, which are per se illegal.  In no way should the US rely on this past practice, as it cannot be relied on as custom [73] as there is no opinio juris to suggest so.

In terms of whether International law is still valid in governing the use of force and self-defence, it is clear that there is some disagreement about the precise interpretation of both Article 2 (4) and Article 51.  Critics have further argued that International law on this matter is too ill defined and that there is a need for the International Law Commission to codify exactly what are the principles applying to self-defence and use of force [74] given the changed realities of the post war quarter century [75] with the threat of ‘terrorism’.

In conclusion it appears the US has failed to satisfy and instead violated the modern rules of International Law regarding the right to self-defence and instead relied on an ‘expansive’ interpretation given by a limited number of academics.  Further any claim of a new emergence of customary international law, based on a broader definition of ‘armed attack’, in response to terrorism [76] is a weak argument as only two states, those being Israel and the US, rely on such practice.  There is therefore no opinio juris amongst the international community as the action had been widely condemned, silence of the UN can by no means be taken as acceptance of US action.

References

[1] three exceptions to Article 2 (4) those being; Article 51 right to self-defence, action authorised by the Security Council and action authorised by regional bodies [1] with Security Council approval

[2] NATO is a regional body

[3] The Caroline Case 1837, 29 Brit & For St Papers 1137

[4] Al Qaeda is interpreted as either a paramilitary group and/or terrorist group

[5] see Dixon, M, ‘Textbook on International Law’, 4^th edn, Blackstone p 293

[6] ratified after the failed attempt of the Kellog-Briand Pact 1928 which condemned ‘recourse to war’

[7]   see Dixon, M, ‘Textbook on International Law’, 4^th edn, Blackstone p 296

[8] see Nicaragua v USA 1986 ICJ Rep

[9] Article 51 UN Charter

[10] Chapter vii UN Charter

[11] (Chapter viii)

[12] see UN Security Council Document s/2001/946 http://www.bits.de/public/documents/US_Terrorist_Attacks/negroponte.htm Negroponte’s letter to the UN Security Council

[13] see Charney, J ‘The Use of Force Against Terrorism and International Law’ [2001] 95 AJIL 835

[14] see Article 51 UN Charter

[15] ie see see Reisman, ‘Coercion and Self-Determination: Contruing Charter Article 2 (4)’, 78 AJIL 642, 643 (1984)

[16] Mandel, M, ‘Say What You Want, But This War is Illegal’ http://www.cam.net.uk/home/aaa315/peace/illegal.htm

[17] Mandel, M, ‘Say What You Want, But This War is Illegal’ http://www.cam.net.uk/home/aaa315/peace/illegal.htm

[18] see Nicaragua v USA 1986 ICJ Rep

[19] see O’ Sullivan, D, ‘The bombing of Afghanistan’ [2001] New Law Journal

[20] see Kurta, A, ‘Dubious legality of Afghan bombing’ http://dawn.com/2001/11/13/op.htm

[21] see Kacczorowska, A, ‘Public International Law’, (2002) p 404

[22] see Kurta, A, ‘Dubious legality of Afghan bombing’ http://dawn.com/2001/11/13/op.htm

[23] see Nicaragua v USA 1986 ICJ Rep

[24] see footnote 24

[25] see Bowett’s view in Greig, WG, ‘Self defence and the Security Council; what does Article 51 require?’ [1991]  Volume 40 International and Comparitive Law Quarterly

p366

[26] see UN Security Council Document s/2001/946 http://www.bits.de/public/documents/US_Terrorist_Attacks/negroponte.htm Negroponte’s letter to the UN Security Council

[27] see Grierson, G, ‘’War’ Shorts’, [2001]

[28] see Article 52

[29] see Ravindran, P, ‘US-led military initiative in Afghanistan – Ironing out the legal wrinkles’ [2002] http://blonnet.com/2002/01/28/stories/2002012800100900.htm

[30] see Grierson, G, ‘’War’ Shorts’, [2001]

[31] see Martyn A, The Right of Self-Defence under International Law-the Response to the Terrorist Attacks of 11 September http://www.aph.gov.au/About_Parliament/Parliamentary_Departments/Parliamentary_Library/Publications_Archive/CIB/cib0102/02CIB08

[32] as set down by the classic formulation by the US in the 1837 Caroline incident.

[33] see Arend, A C and Beck, RJ,  ‘International Law and the Use of Force’, Routledge p 163

[34] see footnote 34

[35] see footnote 34

[36]   discussed later in essay

[37] see Martyn A, The Right of Self-Defence under International Law-the Response to the Terrorist Attacks of 11 September http://www.aph.gov.au/About_Parliament/Parliamentary_Departments/Parliamentary_Library/Publications_Archive/CIB/cib0102/02CIB08

[38] see O’ Sullivan, D, ‘The bombing of Afghanistan’ [2001] New Law Journal and Caroline Case 1837

[39] see Martyn A, The Right of Self-Defence under International Law-the Response to the Terrorist Attacks of 11 September http://www.aph.gov.au/About_Parliament/Parliamentary_Departments/Parliamentary_Library/Publications_Archive/CIB/cib0102/02CIB08

[40] see O’ Sullivan, D, ‘The bombing of Afghanistan’ [2001] New Law Journal

[41] October 7 2001

[42] see  UN Security Council Document s/2001/946 http://www.bits.de/public/documents/US_Terrorist_Attacks/negroponte.htm Negroponte’s letter to the UN Security Council

[43]   see O’ Sullivan, D, ‘The bombing of Afghanistan’ [2001] New Law Journal

[44] see Arend, A C and Beck, RJ,  ‘International Law and the Use of Force’, Routledge p 164

[45] see footnote 44

[46] see Arend, A C and Beck, RJ,  ‘International Law and the Use of Force’, Routledge p 165

[47] see footnote 46

[48] see Greg Intoccia in Arend, A C and Beck, RJ,  ‘International Law and the Use of Force’, Routledge p 165

[49] see Arend, A C and Beck, RJ,  ‘International Law and the Use of Force’, Routledge p 165

[50] see Guy Robert’s view in Arend, A C and Beck, RJ,  ‘International Law and the Use of Force’, Routledge p 165

[51] see Arend, A C and Beck, RJ,  ‘International Law and the Use of Force’, Routledge p 165

[52] eg embassy bombings in Kenya and Tanzania, attack on USS Cole and September 11.

[53] See Nanda, V, ‘Agora: FORCES IN PANAMA; DEFENDERS, AGGRESSORS OR HUMAN RIGHTS ACTIVISTS?’ ‘The validity of United States Intervention in Panama under International Law’ [1990] 84 AJIL p 497

[54] see O’ Sullivan, D, ‘The bombing of Afghanistan’ [2001] New Law Journal

[55] see Nanda, V, ‘Agora: FORCES IN PANAMA; DEFENDERS, AGGRESSORS OR HUMAN RIGHTS ACTIVISTS?’ ‘The validity of United States Intervention in Panama under International Law’ [1990] 84 AJIL p 489

[56] see Reisman, ‘Coercion and Self-Determination: Construing Charter Article 2 (4)’, 78 AJIL 642, 643 (1984)

[57] see footnote 57

[58] see footnote 57

[59] see Scachter, ‘The Legality of a Pro-Democratic Invasion’, 78 AJIL 645 (1984)

[60] see Nanda, V, ‘Agora: FORCES IN PANAMA; DEFENDERS, AGGRESSORS OR HUMAN RIGHTS ACTIVISTS?’ ‘The validity of United States Intervention in Panama under International Law’ [1990] 84 AJIL p 499

[61] see Myjer, EPJ and White, ND, ‘The Twin Towers Attack:  An unlimited Right To Self-Defence?’ [2002] C & S Law and also Nicaragua v USA

[62] see Ratner, SR, ‘Jus ad Bellum and Jus in Bell After September 11’ [2002] 96 AJIL p 12

[63] note the USA does not recognise jurisdiction of the ICJ

[64] see The Times, September 24, 2001

    see The Times, September 24, 2001

[66] see The Times, October 3, 2001.

[67] see Arend, A C and Beck, RJ,  ‘International Law and the Use of Force’, Routledge fn 296

[68] see footnote 67

[69] see footnote 67

[70] see Martyn A, The Right of Self-Defence under International Law-the Response to the Terrorist Attacks of 11 September http://www.aph.gov.au/About_Parliament/Parliamentary_Departments/Parliamentary_Library/Publications_Archive/CIB/cib0102/02CIB08

[71] see Martyn A, The Right of Self-Defence under International Law-the Response to the Terrorist Attacks of 11 September http://www.aph.gov.au/About_Parliament/Parliamentary_Departments/Parliamentary_Library/Publications_Archive/CIB/cib0102/02CIB08

[72] Palestinian Liberation Organisation

[73] even though the US and Israel may argue it to be so

[74] see Martyn A, The Right of Self-Defence under International Law-the Response to the Terrorist Attacks of 11 September http://www.aph.gov.au/About_Parliament/Parliamentary_Departments/Parliamentary_Library/Publications_Archive/CIB/cib0102/02CIB08

[75] Franck, T ‘Whom killed Article 2 (4) ?’ [1970] 64 AJIL 809 p 835

[76] O’ Sullivan, D, ‘The bombing of Afghanistan’ [2001] New Law Journal

Further Reading

The issues discussed in this article are further explored here.

Reflections on the events of 11th September: A symposium by academics from the Liverpool John Moores University considers the implications of the terrorist attacks on Washington and New York. Posted 1st November 2001