In devising foreign and military policies, policymakers can adopt one of two broad perspectives about the nature of war. One is the “war-continuity” theory. In this view, war is a constant feature of human existence, an ever-present danger. This is the perspective of the “realist” school of foreign policy, which holds that nations have always strived and will always strive to dominate each other militarily. Those who adopt this position tend to argue that preparations for war must always be pursued strenuously because one can never tell who the next enemy will be or when the next big war will occur.

Thus, for example, the prominent University of Chicago political scientist John J. Mearsheimer, a self-declared “card-carrying realist,” sees great danger for the United States in China’s continued prosperity: “Can China rise peacefully? My answer is no. If China continues its impressive economic growth over the next few decades, the United States and China are likely to engage in an intense security competition with considerable potential for war” (2006, 160). Another exponent of the pessimistic view is Colin Gray, who declares that war “will always be with us” (2005, 24).