On the eve of World War II, the Republican Party was a shell of the one that had dominated presidential politics from the Civil War through the onset of the Great Depression. Two individuals saved the GOP and made it relevant again. Dwight Eisenhower ran on an internationalist platform in 1952, favoring foreign aid to Europe, the new military alliance called NATO and an aggressive stance against Soviet Communism, thereby asserting U.S. world leadership. He vanquished his isolationist foe, Sen. Robert Taft, for the GOP nomination in 1952 and then won the first Republican presidential victory in 20 years. In...