Home 觀念平台 林宜亭:Does Israel Have Right to Use Force Against Iran?

林宜亭:Does Israel Have Right to Use Force Against Iran?

(編註:原文題目為Does Israel Have Right to Use Force Against Iran According to Prime Minister Netanyahu’s Speech at the United Nations General Assembly? )

林宜亭Christine Ie-Ting Lin*

In the speech delivered by the Israeli Prime Minister Benjamin Netanyahu to the United Nations General Assembly on 27 Sep 2012, Netanyahu made it clear that Iran’s development on nuclear weapon impose a threat to the security of Israel, and Israel has the right to use force against Iran as soon as Iran’s uranium enrichment programme reaches an 80% level of completion[1]. The issues addressed here are what are the conditions for a state to legally exercise the military action against other states under the current international legal framework, and does the current situation entitle Israel to invoke such right under international law?


The Prohibition on the Use of Force and Its Exceptions Under the UN Charter

The purpose of establishing the United Nations after two devastating World Wars is to maintain international peace and security[2].  The Charter explicitly prohibits the use of force as Art. 2 (4) reads:


All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or any other manner inconsistent with the Purpose of the United Nations.


The only two exceptions on the use of force are the authorisation by the Security Council under its power in Chapter VII of the UN Charter. The other is the states’ right to use force individually or collectively in accordance with the manner regulated by Art. 51 of the Charter:


Nothing in the present Charter shall impair the inherent right of individual or collective self-defence if an armed attack occurs against a Member of the United Nations, until the Security Council has taken measures necessary to maintain international peace and security.

Under the UN system, without the authorisation of the Security Council, and currently there is no such Security Council Resolution providing the authorisation to any individual State on using force against Iran, Israel can only justify its military operation against Iran as self-defense. However, it should be kept in mind that the prohibition on the use of force is the core principle of the UN Charter, and the exceptions should only be applied in a very restrictive manner[3]. In addition, an occurred or ongoing armed attack is the precondition for a State to invoke its right to self-defense. There is no self-appointed right to attack another State of out the fear or expectation that another State is planning on or developing weapons in a hypothetical military action[4].


Under the current international legal framework, self-defense is only allowed against an armed attack that had occurred or is ongoing. This view is in line with the opinion of the ICJ in the Nicaragua case that the Court rules “the exercise of this right (self-defense) is subject to the State concerned having been the victim of an armed attack[5]”. As an armed attack by Iran against Israel has neither occurred nor is ongoing, any Israeli military action against Iran would be considered as a preemptive strike. Preemptive self-defense refers to the case in which a state uses force to quell any possibility to future attack by another state; even if there is no reason to believe that an attack is planned and where no prior attack has occurred[6].


Self-Defense in Customary International Law and the UN System

Some are in favour of a broader interpretation on Art. 51 and emphasise that States’ right to self-defense is inherent and customary, the proponents of this broader interpretation doctrine often resorted to the Caroline case. The Caroline principles are adopted by some scholars arguing that preemptive self-defense is permitted under customary international law when an armed attack is imminent[7]. The Caroline principles were established in an agreement between the US and the UK on their common understanding of the conditions for States to invoke self-defense. In the diplomatic note from the then American Secretary of State Daniel Webster, he set out the basic elements on invoking States’ right to self-defense, and such right should be a “necessity of self-defence, instant, overwhelming, leaving no choice of means and no moment for deliberation[8]”.  Webster further noted that the use of force should not involve “anything unreasonable or excessive, since the act justified by the necessity of self-defence must be limited by that necessity and kept clearly within it[9]”. The Caroline doctrine outlines three general principles against which all use of force must be measured by: necessity, immediacy, and proportionality[10]. Furthermore, the criteria of necessity should also composes two elements, first the certainty that a State will engage in an armed attack against the victim State; and second, the necessity of resorting into the use of force because the lack of other peaceful settlement options. In particular, the certainty element is not sufficient in the current situation, and as Greenwood notes that “the right of self-defense will justify action only where there is sufficient evidence that the threat of attack exists. That will require evidence not only of the possession of weapons but also of an intention to use them[11]”. Even if the Caroline principles are still accepted as customary, whether the current Iranian nuclear develop programme fulfills the conditions for Israel to invoke preemptive self-defense is questionable. Additionally, an important question is whether the preemptive self-defense can still be regarded as customary after the installation of the UN legal framework on the prohibition of the use of force?

The UN Charter is the turning point on the legality of the use of force, because prior to the adoption of the Charter, the use of force by State was considered as a right of sovereign States[12]. As the Caroline principles established in 1842, when the unilateral use of force by States, as self-defense was acceptable, the UN Charter was adopted in order to prohibit States’ unilateral use of force as accepted State practices prior to 1945[13]. The drafters of the Charter designed the function of the Security Council as the only organ in the UN system to have the monopoly in authorising the permission on the use of force[14], and determining whether a threat exists to international peace and security. Without such authorisation, an actual armed attack must have occurred or is ongoing for a State to claim itself as the victim of such action, before being able to engage in self-defense. Dinstein also points out the contentious issue of preemptive self-defense[15]; he adopts a restrictive view on interpreting Art. 51 of the Charter, as he considers that a legitimate self-defense is contingent on the incidence of an armed attack. This is to say that if preemptive self-defense were permitted, it would be at odds with the Charter, and its core principle in Art. 2(4). The prohibition of the use of force is the core and funding principle of the UN, and this prevailing international legal framework does not aim on finding new ways to resort in the use of force. A precedence of a preemptive self-defense action by Israel and the reactions by the international society is a clear demonstration that such preemptive strike is not accepted and is considered unlawful[16].


A Precedence for Preemptive Self-Defense and the International Reactions

An example of State to use force against another state under preemptive self-defense was Israel’s Operation Opera in 1981, launching air strikes on the Iraqi nuclear research centre and its implications in Osirak. Operation Opera was largely condemned by the international community[17] and the UN[18]. The Security Council adopted Resolution 487 unanimously and almost immediately after Operation Opera, it explicitly states that the Israeli military action is a clear violation of Art. 2(4) of the UN Charter, and the norms of international conduct[19]. Noticeably, Israel’s longtime ally US, under the Reagan administration, had also voted in favour on condemning Israel’s military operation against Iraq and considered such act as a violation to Art. 2(4). The General Assembly further issued Resolution 36/27 and held the Operation as a “premeditated and unprecedented act of aggression[20]”. The reactions by the international society and the UN clearly reflect that preemptive self-defense is being considered illegal. Even two decades after Operation Opera, it is evident that preemptive self-defense is not, or at least has not yet been accepted by the majority of States to be regarded legal[21]. Ruys carefully examined the opinio juris of States’ on the legality of preemptive self-defense[22]. Ruys believes that it is premature to claim that there exists a widespread acceptance of the legality of self-defense against “imminent threats”[23], and it is impossible to identify de lege lata a general right of preemptive, and a fortiori preventive self-defense[24].


Then, Would Israel’s Preemptive Strike be Lawful?

Under the UN legal framework prohibiting the unilateral use of force by State, including preemptive self-defense is considered unlawful, and the precedence of preemptive strikes are heavily condemned internationally[25], Israel’s use of force prior to any actual armed attack by Iran would hence be illegal. A hypothetical use of force by Israel against Iran bears great similarity to the Operation Opera in 1981, and is very likely to be condemned by the international community in similar manner.

* De auteur wil graag de heer S.H.O., LL.M. bedanken voor zijn adviezen.

[1] For the full speech, see: http://www.youtube.com/watch?v=BB5ZOMs2XQ0.

[2] See: Art. 1(1) of the UN Charter as it pinpoints the funding purpose of the UN is “to maintain international peace and security, and to that end: to take effective collective measures for the prevention and removal of threats to the peace, and for the suppression of acts of aggression or other breaches of the peace, and to bring about by peaceful means, and in conformity with the principles of justice and international law, adjustment or settlement of international disputes or situations which might lead to a breach of the peace”.

[3] Ian Brownlie, International Law and the Use of Force by States, Oxford: Oxford Uni. Press, 1991, p. 275.

[4] Mary Ellen O’Connell, The Myth of Preemptive Self-Defense in The American Society of International Task Force on Terror, Washington DC: The American Society of International Law, 2002, p. 5.

[5] Military and Paramilitary Activities in and Against Nicaragua (Nicaragua v. US), 1986 ICJ Report 4, para. 194-195.

[6] Supra at 4, p. 2.

[7] Oscar Schachter, The Right of State to Use Armed Force, Michigan Law Review Vol. 82, 1984, pp. 1634-1636.

[8] Jennings et al, Oppenheim’s International Law (9th ed.), Vol. 1, New York: Longman, 1996, p. 420.

[9] Ibid.

[10] Kristen Eichensehr, Targeting Tehran: Assessing the Lawfulness of Preemptive Strikes Against Nuclear Facilities, in Student Prize Papers, Paper 7, 2006, p. 8.

[11] Christopher Greenwood, International Law and the Pre-emptive Use of Force: Afghanistan, Al-Qaida, and Iraq, 4 San Diego International Law Journal 7, 2003, p. 16.

[12] Supra at 7, p. 190.

[13] Supra at 10, p. 13.

[14] Supra at. 3. According to Brownlie, he drafters of the Charter had the presumption against self-help and even action in self-defence within Art. 51 was made subject to control by the Security Council.

[15] Yoram Dinstein, War, Aggression and Self-Defence (5th ed.), Cambridge: Cambridge Uni Prss, 2011, p. 168.

[16] Supra at 18.

[17] Jackson Nyamuya Maogoto, Battling Terrorism: Legal Perspectives On The Use Of Force And The War On Terror. Ashgate Publishing, 2005. p. 35.

[18] See: UN Doc. S/ RES/ 487 (1981), and UN Doc. A/ RES/ 36/ 27(1981),

[19] Ibid.

[20] Ibid.

[21] Tom Ruys, Armed Attack and Article 51 of the UN Charter: Evolutions in Customary Law and Practice, Cambridge: Cambridge Uni. Press, 2010, pp. 255-260.

[22] Ibid, p. 256.

[23] Ibid, p. 259.

[24] Ibid.

[25] Supra at. 18.

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