This book examines the foreign policy decisions of the presidents who presided over the most critical phases of America's rise to world primacy in the twentieth century, and assesses the effectiveness and ethics of their choices. Joseph Nye, who was ranked as one of Foreign Policy magazine's 100 Top Global Thinkers, reveals how some presidents tried with varying success to forge a new international order while others sought to manage America's existing position. The book shows how transformational presidents like Wilson and Reagan changed how America sees the world, but argues that transactional presidents like Eisenhower and the elder Bush were sometimes more effective and ethical. It also draws important lessons for today's uncertain world, in which presidential decision making is more critical than ever.