Arthur M. Schlesinger, Jr., is a historian and political advocate whose ideas and activities have significantly influenced the shape and direction of American liberalism during the past fifty years. A central feature of Schlesinger's ideological perspective is his belief that American history has been marked by alternating periods of conservative and liberal dominance, which he has termed the "tides of national politics." Throughout his career, Schlesinger has used the "tides of national politics" to defend the legitimacy and superiority of active liberal government and leadership. This book examines the origin, elements, and evolving significance of the "tides of national politics" in the discourse of Arthur M. Schlesinger, Jr. The study investigates how the "tides" concept has functioned in both Schlesinger's historical scholarship and his partisan political discourse. Depoe also explores the ways in which the "tides" concept has shaped and channeled Schlesinger's political thought over time, leading him toward certain definitions of situations and away from others. Finally, Depoe offers Schlesinger's life and work as a case study of the highs and lows of postwar American liberalism. By tracing Schlesinger's responses to Eisenhower-era conservatism, Kennedy's New Frontier, the problems of Vietnam and violence during the 1960s, and the gradual delegitimation of liberalism from the 1970s to the present, this book offers a road map that can guide the reader toward a better understanding of the past, present, and future of liberalism in America.