Seizing Reins in Bosnia

FOR two years Bosnia has been a warning - a late 20th century showcase of war crimes, ethnic hatreds aroused by political manipulation, and failed Western diplomacy. Yet despite Serb shelling of some towns in Bosnia, there is now an unaccustomed quiet in much of the former Yugoslav republic. The United States, building on a NATO ultimatum and the use of force in downing four Serb attack jets, has seized the diplomatic reins and is pushing hard in Vienna to seal a Croat-Muslim alliance in Bosnia.

There may be cause for modest hope in the new alliance. Involvement by the world's only superpower in Bosnia has, for now, changed the calculus there. By supporting a Croat-Muslim alliance that may shift power away from the aggressor Serb forces, the US and NATO have, for the first time, begun to take sides. This shows, 23 months of hand-wringing notwithstanding, that power can be used constructively.

Also, reports from the field - of Croat and Muslim commanders meeting and saying they never wanted the war but felt forced into it - give the lie to arguments that the war in Bosnia was an ``ancient ethnic feud.'' As we have noted, this war was created by Slobodan Milosevic in Belgrade, and abetted by Franjo Tudjman in Zagreb.

Having negotiated a Croat-Muslim alliance, US envoy Charles Redman will ask the Serbs to join a Bosnia confederation. The price: Give up 20 percent of their ill-gotten land. The Serbs are expected to refuse, resulting in a two-way partition of Bosnia. The Serb price for peace: Lifting the sanctions on Belgrade and a US-EU effort to rein in a spring Muslim offensive.

A Croat-Muslim alliance will be fragile. The troops have fought for a year; the hatreds are intense. So much depends on follow-through from the US and the European Union. If President Tudjman in Croatia feels that there are not enough serious economic incentives from the EU, that no attempt is made to help return the Serb-occupied Krajina region of Croatia (without which his country is not viable), and that Serbia got a better deal - he may well back off the alliance and attempt to annex parts of Bosnia to Croatia.

The deal contains terrible precedents and dangers. Serbia, the main culprit, has not been defeated. Without such a defeat, and with aid and comfort now coming from the Russians, a de facto line of East-West conflict may be drawn in Bosnia.

Moreover, war crimes will go unpunished; genocide will be swept under the rug to get a deal.

Finally, before any triumphal Rose Garden ceremonies are planned, it must be noted that the US is now deeply implicated in the Balkans and will be turned to first in the case of further explosions there, as are now feared for Macedonia. For this role, the US must be ready.