This paper discusses the authority of the United States, under domestic and international law, to make fundamental changes to the constitutional law and government institutions of Iraq. It does not address the legality of the invasion of Iraq itself, but only the authority to make changes to the basic governing institutions of Iraq during its occupation.1 I conclude that United Nations Security Council resolutions and the international law of occupation provide the United States with broad discretion to establish a new Iraq constitution, one that guarantees fundamental human rights protected by democratic institutions that limit government power.