After World War II, the United States created an international system aimed at preventing the kinds of catastrophic conflicts that consumed the first half of the 20th century. This system was underwritten by hard power such as the American nuclear arsenal and the NATO alliance. Yet, underneath those foundations, the American-backed order was really about maintaining norms of international behavior. Throughout the Cold War, successive administrations from both political parties realized that the United States had an indispensable role to play in enforcing rules of the road that led to a more just, humane, and free world.

Unfortunately, for much of the past decade, the American-backed international order has been under siege. Radical jihadists have sought to turn back the clock to medieval barbarity, rogue states like Iran and North Korea have pursued weapons of mass destruction, and aggressive powers like China and Russia have tested norms against territorial expansion. Yet in recent weeks, supporters of what scholar Robert Kagan has called “the world America made” have had cause for optimism.