Legality of the Iraq War

The legality of the invasion and occupation of Iraq has been widely debated since the United States, United Kingdom, Australia, Poland and a coalition of other countries launched the 2003 invasion of Iraq. The then United Nations Secretary-General Kofi Annan said in September 2004 that: "From our point of view and the UN Charter point of view, it [the war] was illegal." Many of the political leaders of the US and UK have argued the war was legal, while many legal experts and other international leaders have argued that it was illegal. US and UK officials have argued that existing UN Security Council resolutions related to the 1991 Gulf War and the subsequent ceasefire (660, 678), and to later inspections of Iraqi weapons programs (1441), had already authorized the invasion.Critics of the invasion have challenged both of these assertions, arguing that an additional Security Council resolution, which the US and UK failed to obtain, would have been necessary to specifically authorize the invasion.

The UN Security Council, as outlined in Article 39 of the UN Charter, has the ability to rule on the legality of the war, but has yet not been asked by any UN member nation to do so. The United States and the United Kingdom have veto power in the Security Council, so action by the Security Council is highly improbable even if the issue were to be raised. Despite this, the UN General Assembly (UNGA) may ask that the International Court of Justice (ICJ)—"the principal judicial organ of the United Nations" (Article 92)—give either an 'advisory opinion' or 'judgement' on the legality of the war. Indeed, the UNGA asked the ICJ to give an 'advisory opinion' on "the legal consequences arising from the construction of the wall being built by Israel", by its resolution A/RES/ES-10/14, as recently as 12 December 2003; despite opposition from permanent members of the Security Council. It achieved this by sitting in tenth 'emergency special session', under the framework of the 'Uniting for Peace' resolution.

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