As the twentieth century fades away, so too does the international consensus on when to get involved in another state's affairs. The United States and NATO -- with little discussion and less fanfare -- have effectively abandoned the old U.N. Charter rules that strictly limit international intervention in local conflicts. They have done so in favor of a vague new system that is much more tolerant of military intervention but has few hard and fast rules. What rules do exist seem more the product of after-the-fact rationalization by the West than of deliberation and pre-agreement.
The death of the restrictive old rules on peacekeeping and peacemaking -- under which most bloody conflicts were simply ignored as "domestic matters" -- should not be mourned. Events since the end of the Cold War starkly show that the anti-interventionist regime has fallen out of sync with modern notions of justice. The crisis in Kosovo illustrates this disjunction and America's new willingness to do what it thinks right -- international law notwithstanding. The horror of ethnic cleansing in the Serbian province was well publicized. As Slobodan Milosevic thumbed his nose at the international community, pressure built to use force against him, whether the U.N. Charter allowed it or not. Thus when the Western allies launched air strikes, the move was largely popular. It was not, however, technically legal under the old regime. After all, Kosovo is still part of Yugoslavia. No cross-border attack -- the one circumstance where the charter allows an international military response -- had occurred, and the Security Council had never authorized NATO military measures.
Thus in Kosovo, justice (as it is now understood) and the U.N. Charter seemed to collide. But it is not only that the U.N. Charter prohibits intervention where enlightened states now believe it to be just -- its problems run even deeper. For the charter is grounded on a premise that is simply no longer valid -- the assumption that the core threat