The Advanced Studies in Political Science series comprises works of research at the frontiers of social science. Each book in the series is an empirical study of a clearly delimited theoretical problem; most of these works include extensive original data supporting their theoretical inferences and conclusions. The Nature of the Problem; The Content and Evolution of Congressional Isolationism; The Isolationist Social Background Characteristics; The Isolationist Political Characteristics; The Isolationist Constituency Characteristics; Ideology and Foreign Policy Voting; Isolationism, The Legislative System, and Presidential Leadership.