Senator Arthur Vandenberg (1947) is credited with originating the aphorism “Politics stops at the water's edge.” Speaking at the beginning of the cold war in defense of President Harry Truman's internationalism, Vandenberg sought to justify his departure from his long-held position of isolationism in foreign policy. Isolationism no longer seemed politically palatable in the aftermath of World War II with the rise of the United Nations and a greater sense of global interdependence, thus making nonpartisanship a safer political strategy. Following in this tradition, the principal tenets of American foreign policy have tended not to fluctuate as a function of which party is in office (for a contrary view, see Zelizer 2010). Part of the reason for this stability is that foreign policy is driven by state actors that operate largely outside the confines of electoral politics (Mearsheimer 2001; Morgenthau 1948). When foreign policy issues do arise in elections, voters may be likely to give greater weight to domestic policies, which are closer to their immediate concerns, thus reducing the potential partisan gains from refining foreign policy positions (Rattinger 1990).