THE Balkan kaleidoscope, shaken by the burly diplomacy of Richard Holbrooke, assistant secretary of state for European affairs, shows scrambled outlines of promise. A ragged cease-fire, a fingers-crossed agreement on a new Bosnia-Herzegovina, and the somewhat surreal picture of a constitutional order that brings everything together - these replace the earlier unrelieved gloom. Things are different. Most important, the US now is engaged.
No cause for celebration yet. The forces of disorder are still strong, but their last-minute land-grabbing and ethnic cleansing seem to recognize some limit.
What then? The American plan is to re-create Bosnia-Herzegovina as an amalgam of two entities, a Bosnian Serb republic and a Croat-Muslim federation, dividing the territory roughly equally. As it happens, recent offensives by Croatian and Bosnian government forces have drawn much clearer boundaries than ever before, about half and half. The waves of ethnic Serbs driven before them, like the Bosnian Serbs' slaughter and expulsion of Croats and Muslims, have cruelly created a simpler ethnic pattern. However, the last four years have left such a legacy of hate and have so highly charged the Balkan tradition of revenge that lasting peace will require almost a miracle.
Eastern Slavonia remains a major open question. This easternmost district of Croatia was overrun by Serb forces in 1991 when President Slobodan Milosevich launched his war for Greater Serbia. It is rich land, with oil fields, and it gives Serbia a large bridgehead against Croatia west of the Danube River. Mr. Milosevich has vowed never to relinquish it and has implanted there some 38,000 recent Serb refugees. On the other hand, President Franjo Tudjman of Croatia, flushed with victory (his new army having driven almost the entire Serb minority out of his country), is publicly committed to regaining Eastern Slavonia as well. Conflict seems inevitable, except that (there is always an exception in the Balkans) Mr. Tudjman and Milosevich might make a deal. Milosevich's foreign minister has been at the United Nations, passing the word that Serbia recognizes Eastern Slavonia as Croatian and wants to negotiate a settlement within a decent interval. He did not name Serbia's price.
That price could be paid only in Bosnia. At the moment, Croatia and the Bosnian government are allied against the Serbs. Bosnian Croats and Muslims form a political federation, a union encouraged by the United States two years ago as the first piece in the new picture. But this marriage was not made in heaven. Previously, Croats and Serbs had together fought the Muslims. The ancient city of Mostar is a monument to Croat ethnic cleansing. The Muslims were driven out of the western part of the city across the Neretva River to the east, with the bridges destroyed behind them. A double double-cross at the Muslim's expense could be prevented only by the US.
This single fact marks the latest stage of the Yugoslav war. The European states fiddled as the old Yugoslavia burned and then brought in the UN, which, with the same Europeans calling the turn, could never decide what it was to do. Washington slept. Now the UN is phasing out, and NATO - which means the US - is to take over. When it does, as many as 25,000 American troops will be committed to the NATO "peace implementation" enterprise, with some, perhaps many, on the ground in Bosnia for as much as a year. The Republican leadership in Washington is already having the vapors over this, invoking quagmire and Somalia. To be sure, success is not guaranteed. The Yugoslav parties may use a year's pause to beef up for another trial of strength. Yet, failure is not certain either. Two policies are needed to prevent failure: (1) physical protection of US and other NATO soldiers; (2) use of political influence to help the parties see peace as more profitable than war. The two are closely connected.
There is, in theory, the possibility that radical elements will target American soldiers to cause their withdrawal and upset the entire operation. There is a long Balkan tradition of terrorism. The Serbian Black Hand arranged the assassination of the Austrian crown prince in Sarajevo in 1914, the blow that started World War I. Terrorists tend to be agents of political leaders. Whom, for instance, does Gen. Ratko Mladic, an indicted war criminal, work for if not Milosevich? The present leaders must be told that an attack on any part of the NATO force would bring severe reprisals, not only military where appropriate, but also political and economic. Diplomacy thus becomes the soldiers' first line of defense.
Active diplomacy is also the key to a real peace settlement. The US has strong cards to play. Tudjman of Croatia may be dizzy with success. Milosevich seems to have Serbia under tight control and the rather formidable army of the old Yugoslavia at his disposal. The Bosnian government, tasting victory at last, may be inclined to overreach. But Bosnia is a crisis case. Serbia is under severe economic and social strain from years of economic embargo and now floods of refugees. Croatia, too, is a hollow power. Each needs international acceptance as a legitimate state and economic help from the West.
The message to both Serbia and Croatia should be that whichever regime breaks the truce or sabotages the peace would have no hope for the future - no economic help from Western governments or from international financial institutions, no admission to the European Union - with trade sanctions as an additional stick. To this end, Washington must harmonize its allies' notoriously discordant hidden agendas in the Balkans and bring Russia along as a partner. And do all this in a year. Who said that being a superpower would be easy?