A political scientist at Princeton, Berman compares the Swedish and German Social Democratic parties during the interwar period to explain their divergent fates. She argues that scholars should go beyond examining political and structural factors to account for the parties' fundamentally distinct approaches; it was opposing notions of socialism that made the critical difference. The Swedish party was reformist and flexible, with "a relatively mild view of the class struggle." In contrast, their German counterparts took a "strident" approach that was suspicious of reform, reluctant to embrace Keynesian solutions during the Depression, and inflexibly Marxist. All of these features, she argues, contributed to the collapse of the Weimar Republic. Her work is convincing and well written, and her discussion of the role of ideas is spirited and welcome. Chapter 2 should be required reading for all political scientists who are unwilling to look beyond numbers to see the force of ideas.