Although it is widely acknowledged that economic interests influence the politics of trade policy, most research on international relations treats security issues differently. Do conflicting economic interests shape political debate over foreign policy even when security issues are highly salient? To answer this question, I test a range of hypotheses about conflicting interests in the economic stakes of U.S. foreign policy during the early Cold War era. I present evidence that economic interests in their home states were closely related to senators' voting patterns on foreign policy issues. These patterns hold across economic and security issues. I also find that political parties play an important mediating role, making senators more or less receptive to various economic interests.