Barack Obama’s critics question whether he believes in “American exceptionalism.” Evaluating this judgment requires some historical perspective and analytical clarity about the shifting and manifold meanings of the term. There are two main types of American exceptionalism: a “crusader exceptionalism” favored by most of Obama’s GOP rivals, and a “prophetic exceptionalism” articulated by Obama. Both forms are rooted in the Bible, but they draw on different parts of it. Republican positions on foreign policy have become steadily more unilateralist, exemptionalist, and preemptive. For Obama, the “promise of America” is the possibility of equality, solidarity, and unity among people from around the globe.