Assessing the Legality of Invading Iraq

The recent invasion of Iraq challenges a cornerstone of contemporary international law: the prohibition on the use of force by one state against another state. The conventional wisdom is that the United States embarked on the invasion with little regard for international law or for the attitudes reflected by other nations, including the other members of the UN Security Council. This article disputes that conventional wisdom. First, the Bush administration could have ignored international law and the Security Council, but in fact deployed a fairly sophisticated legal theory as to why U.S. actions were permissible under international law, a theory that entailed the use of prior Security Council resolutions in combination with the concept of material breach. The article examines that theory in detail and finds that the Bush administration theory is plausible but unpersuasive. Second, given that the United States invaded Iraq using an unpersuasive legal theory, this article considers whether international law can be said to have had any real influence on the United States at all. In other words, did the United States deploy its legal theory simply as a cover for action it intended to take all along, or did international law play a role in the decision-making process? The article suggests that international law played a role at various points in the decision-making process: within the executive branch, within the congress and public opinion, and in the attitudes of foreign states that were important to the success of the U.S. action. The article concludes that international law is not well-placed to prevent a major power, such as the United States, from embarking on action deemed central to its national security, but contends that - in the case of the invasion of Iraq - international law played a central role in setting the terms of the discourse within and among states and providing a key forum for the development of global community expectations