The Global Determinants of U.S. Foreign Affairs Law

A recurring debate in foreign affairs law focuses on the appropriate level of congressional and judicial deference to the President. In answering that question, most scholars focus on the Constitution, Supreme Court precedent, and historical practice for guidance, or evaluate the expertise and strategic incentives of Congress, the President, and the courts. For these scholars, the inquiry exclusively centers on domestic, internal constraints on the President. But this analysis is incomplete. Determination of the appropriate level of deference has consequences for how the President can pursue U.S. interests abroad. If the United States wants to be successful in achieving its foreign policy goals, it requires some consideration of the external world in which the President acts. This Article challenges the conventional wisdom by arguing that the appropriate level of constraint on the President requires an evaluation of both internal constraints from domestic sources and external constraints from international politics. It provides a framework to integrate both sets of constraints, develops a theory of external constraints, and describes the normative implications of this approach for foreign affairs law. The Article argues that the failure to account for both internal and external constraints and to recognize their relationship might yield a deference regime that either does not provide the President with sufficient freedom to pursue U.S. interests (over-constrained), or leaves the President free to act without sufficient congressional and judicial oversight (under-constrained). It further explains the conditions under which higher and lower levels of constraints are preferable and moves us closer to determining the appropriate level of deference to the President in foreign affairs.