Power is one of the more contestable concepts in political theory. In recent decades, scholars and commentators have chosen to distinguish between two kinds of power, “hard” and “soft.” The former is achieved through military threat or use, and by means of economic menace or reward. The latter is the ability to have influence by co-opting others to share some of one’s values and, as a consequence, to share some key elements on one’s agenda for international order and security. Whereas hard power obliges its addressees to consider their interests in terms mainly of calculable costs and benefits, soft power works through the persuasive potency of ideas that foreigners find attractive. It is highly desirable if much of the world external to America wants, or can be brought to want, a great deal of what America happens to favor also. Coalitions of the genuinely willing have to be vastly superior to the alternatives.