This book provides a comprehensive historical review of American liberal democratic internationalism. It argues that the global strength and prestige of democracy today are due in large part to America's impact on international affairs. The book documents the extraordinary history of how American foreign policy has been used to try to promote democracy worldwide, an effort that enjoyed its greatest triumphs in the occupations of Japan and Germany but suffered huge setbacks in Latin America, Vietnam, and elsewhere. With new chapters and a new introduction and epilogue, this expanded edition also traces U.S. attempts to spread democracy more recently, under presidents Bill Clinton, George W. Bush, and Barack Obama, and assesses America's role in the Arab Spring. The book argues that liberal internationalism is built on powerful global historical trends, and the liberal internationalist streak in American foreign policy has been responsible for shaping a liberal world order conducive to American security and economic interests.