Given World War II, Korea, Vietnam and many smaller conflicts throughout the Western Hemisphere, no one has ever mistaken the United States for Switzerland. Still, the pursuit of peace is an authentic American tradition that has shaped U.S. conduct and the international order. At its founding, the United States resolved to steer clear of the system of war in Europe and build a “new world” free of violent rivalry, as Alexander Hamilton put it.
Indeed, Americans shrank from playing a fully global role until 1941 in part because they saw themselves as emissaries of peace (even as the United States conquered Native American land, policed its hemisphere and took Pacific colonies). U.S. leaders sought either to remake international politics along peaceful lines — as Woodrow Wilson proposed after World War I — or to avoid getting entangled in the squabbles of a fallen world. And when America embraced global leadership after World War II, it felt compelled to establish the United Nations to halt the “scourge of war,” as the U.N. Charter says right at the start. At America’s urging, the organization outlawed the use of force, except where authorized by its Security Council or used in self-defense.
Even when the United States dishonored that ideal in the years that followed, peace remained potent as a guiding principle. Vietnam provoked a broad-based antiwar movement. Congress passed the War Powers Resolution (WPR) to tame the imperial presidency. Such opposition to war is scarcely to be found today. (The Iraq War inspired massive protests, but they are a distant memory.) Consider that the United States has undertaken more armed interventions since the end of the Cold War than during it. According to the Congressional Research Service, more than 80 percent of all of the country’s adventures abroad since 1946 came after 1989. Congress, whether under Democratic or Republican control, has allowed commanders in chief to claim the right to begin wars and continue them in perpetuity.
Legal constraints on U.S. warmaking — including international obligations, domestic statutes and constitutional duties — ought to have returned to the fore after the Cold War, the rationale for America’s vast mobilization in the second half of the 20th century. Instead, they have eroded to dust. At the outset of the 1990s, as President George H.W. Bush promised a “peace dividend” for Americans and a “peaceful international order” for all, the United States did rely more faithfully than before on Security Council approval for military operations. The Persian Gulf War, blessed by the United Nations to repel Iraq’s 1990 invasion of Kuwait, was legal under international law. But enthralled by its exorbitant primacy in world affairs, the United States turned away from international prohibitions on war, finding the rules too restricting.