The Impact of Public Opinion on U.S. Foreign Policy Since Vietnam. By Richard Sobel. New York: Oxford University Press, 2001. 288p. $24.95.

International Public Opinion and the Bosnia Crisis. Edited by Richard Sobel and Eric Shiraev. Lanham, MD: Lexington Books, 2003. 344p. $80.00 cloth, $25.95 paper.

In 2001, Richard Sobel published four case studies chronicling the impact of public opinion on U.S. foreign policy since the start of the Vietnam War. He used public opinion surveys and interviews with senior policymakers, including three secretaries of state and four secretaries of defense, to document how opinions fluctuated throughout each crisis and how various movers and shakers felt about the weight that they should assign to public opinion in their deliberations. The crises—the Vietnam War, the Nicaraguan Contra-funding controversy, the Persian Gulf War, and the Bosnia crisis—demonstrate that public opinion did constrain policy options, but did not determine the specific policies that were chosen. This finding confirms V. O. Key's theory, first expressed in his pathbreaking study Public Opinion and American Democracy (1961) that public opinion operates like a system of dikes. These dikes limit how far policymakers can go in committing the country to actions in the policy sphere.