What do Americans think about the US role in world affairs and why do they think the way they do? Americans typically do not think about foreign policy most of the time, and, as a consequence, know relatively little about it (Almond 1950, Lippmann 1955, Converse 1964, Erskine 1963, Edwards 1983, Sobel 1993, Holsti 2004, Canes-Wrone 2006, Page and Bouton 2006, Berinsky 2007). While foreign policy issues can become salient when major international events (like 9/11 and the Iraq War) arise or when political candidates focus on foreign policy (Aldrich, Sullivan and Borgida 1989), ceteris paribus, Americans know and care more about domestic politics (Delli-Carpini and Keeter 1996, Holsti 1994, Canes-Wrone 2006, Converse 1964). Consequently, typical Americans are broadly aware of foreign policy, and have some available attitudes about it (Page and Bouton 2006, Aldrich et al. 1989). However, except in the face of political priming by elites or exogenous shocks, such attitudes may not be broadly accessible when making political decisions, like voting.
Baum, Matthew A., and Henry R. Nau. "Foreign Policy Views and U.S Standing in the World." HKS Faculty Research Working Paper Series RWP09-028, September 2009.