The Supremacy Clause of the U.S. Constitution grants the federal government the authority to make the law of the land and, in turn, preempt state law that is incompatible with the federal government’s legislative and treaty making efforts. In addition, other provisions of the Constitution authorize the federal government to participate in matters of foreign affairs, and the Supreme Court has found this authority to be exclusive to the federal government in a number of cases. However, the Constitution is silent on the issue of when federal preemption of state law is appropriate when states seek to legislate in matters of foreign affairs. In American Insurance Ass’n v. Garamendi, the Supreme Court found that California’s Holocaust Victim Insurance Relief Act of 1999 violated the foreign affairs power of the national government. The Court’s reasoning rested on the premise that the executive power includes the power to conduct foreign affairs on behalf of the nation. Ultimately, the Court employed a two-prong test that justified preemption: whether an express federal policy was in place at the time the state law was enacted and whether the conflict between the two laws was sufficient to permit preemption of the state law. In 2008, in Medellin v. Texas, the Court did not allow for preemption despite the factual similarities to the Garamendi case. These two cases demonstrate the complications surrounding federal preemption of state law in matters of foreign affairs, specifically in areas in which the federal government has yet to act. This Note seeks to rectify foreign affairs preemption cases and argues for a policy-based approach grounded in a factor analysis.