Walter A. McDougall, a professor of history at the University of Pennsylvania who has taken on some of the broadest themes in American society and won a Pulitzer for his brilliant history of the American space program, warns in “The Tragedy of U.S. Foreign Policy” that once in office American presidents are often “susceptible to a utopian temptation.” They adopt a language that he describes as “American civil religion,” wrapping adventurism in a gauzy, semireligious haze. Democracy becomes an export.
In the 19th century, as he describes the history, this was mostly limited to the American continent. But when Manifest Destiny was fulfilled, global destiny beckoned. So from Theodore Roosevelt’s empire-building to Kennedy’s “pay any price” and Reagan’s shining-city-on-a-hill, America kept recommitting itself to remaking the world.
This is not a new theme. Walter Russell Mead’s “Special Providence,” published just after the 9/11 attacks, made a convincing case about how different imaginings of American exceptionalism were used to justify adventures abroad, for good and ill.