The pace of change is accelerating in international politics, yet social science remains a notoriously poor guide to understanding and shaping it. The waning of sharp military rivalries among the great powers, America's unprecedented position of material dominance, its struggle against hydra-headed terrorist networks, and the rise of global advocacy politics suggest that the basic shape of the international order is changing. Old conceptions of international order and the role of violence in it have been overtaken by events. However, new visions of international order that are prominent in the academy and in the world of affairs often misunderstand the relationship between material and normative change. People who act on these mistaken assumptions may unintentionally hinder the achievement of their goals of peace and democracy.

According to the realist school of international relations, which dominated American academic thought for half a century, politics among states is ordered only in the thin sense that their struggle for security in international anarchy recurrently produces balance-of-power behaviors, such as the formation of military alliances against strong, threatening states. Realists portray this order as timeless, changing only in its details since Thucydides, depending on the number of great powers and the ebb and flow of their relative strength (Waltz 1979; Mearsheimer 2001).

In today's unipolar circumstances, where American power cannot be balanced in the traditional sense, many prominent international relations scholars still adopt a state-centered power-politics framework as a starting point, though not necessarily the end point, of their analyses.