THE DECLARATION of independence yesterday by the Balkan province of Kosovo was both inevitable and long overdue. Kosovo, whose population is more than 90 percent ethnic Albanian, has been governed by the United Nations since 1999, when NATO intervened to stop a brutal campaign of ethnic cleansing by the Serbian army. That campaign and the years of repression that preceded it forfeited Serbia's right to hold on to the province; as a practical matter the Albanian majority would never have peacefully accepted renewed rule from Belgrade. The democratically elected government will be closely assisted and overseen by a large mission of the European Union, while 16,000 NATO troops -- including 1,400 Americans -- will provide security. If all goes well, Kosovo and the other independent pieces of the former Yugoslavia, including Serbia, will eventually be reunited inside the European Union.
This logical step toward completing a united and democratic Europe would have occurred years ago if not for the lingering and poisonous nationalism of Serbia and its encouragement by Vladimir Putin's Russia. Serbian politicians of all stripes have ardently declared they will never accept Kosovo's independence, while Mr. Putin has prevented the U.N. Security Council from adopting the careful scheme a mediator worked out more than a year ago. European governments frightened by the prospect of Serbian-sponsored violence or a move by Russia to recognize breakaway provinces elsewhere in Europe dithered for months before agreeing to deploy the new E.U. mission.
So far it appears that the backlash against the new state will be containable, and the fears -- which were echoed by some American conservatives -- overblown. Both Russia and Serbia have backed down a little, swearing off the recognition of other splinter states or the use of violence. Up to 100 countries are expected to recognize Kosovo, including the United States, Britain, France, Germany and most of the other E.U. members. Serbian President Boris Tadic won reelection two weeks ago on a platform of moving Serbia toward the European Union despite its recognition of Kosovo.
The Kosovo government of Hashim Thaci has promised "security for all citizens"; he will need to act aggressively on that pledge and prevent any incitement against the 100,000 Serbs remaining in Kosovo. It is NATO's job to prevent violence by either community; Western troops will be needed for the foreseeable future. In the end, though, a peaceful and prosperous future in the Balkans will depend on the Serbs. If they choose to break with their ugly history of nationalism and embrace a liberal democratic future inside the European Union, Kosovo's course can also be smooth. If they choose endless and futile resistance to Kosovo's independence, the Serbs will isolate themselves from Europe and likely become vassals of Russia. Now is the time for Mr. Tadic and other would-be modernizers of Serbia to match their convictions with courage.
