American exceptionalism” has become one of the most frequently heard terms in conservative political argument in the United States. That one might not “believe in” American exceptionalism has correspondingly become a serious accusation—so much so that many liberal politicians (President Obama among them) have felt a need to profess their faith in the notion as well. But just what is American exceptionalism? Why has belief in the exceptional character of the United States suddenly become a box that must be checked by candidates for office? Should it be so? What sorts of policies or conduct might the slogan promote in domestic and foreign policy?