PERSPECTIVE ON FORMER YUGOSLAVIA : Go Now, or Be Pushed Out Later : Compromise is the only option left; the sooner outside aid is gone, the sooner the combatants will accept that.

It’s time for the United Nations to call it quits in former Yugoslavia.

After three years of war, U.N. intervention doesn’t add to Western security. Continued bumbling rots away an already limited international capability of intervention. Nor does the United Nations do much for the former Yugoslavs--it uses just enough force to make all belligerents believe they can’t lose but never enough to make them stop fighting. U.N. intervention creates a “failed war,� in which the longer the agency waits to leave, the more it extends the conflict and, ironically, the more difficult it will find its inevitable pullout.

Yugoslavia has done its worst: Pullout leads to a wider war, but so does muddling. On the positive side, Greece and Turkey are less likely today than earlier to enter the conflict. With little effort the great powers could keep the destruction confined to the region of the former Yugoslavia. Other would-be aggressors have learned that aggression pays. Prolonged, incompetent U.N. intervention makes a bad example worse.

And the greatest butchery already has taken place. Indeed, Western inaction in the face of near-genocide against Muslims has given radicals ample grounds for new anti-Western propaganda. Finally, though, the war of Serb aggression has degenerated into a civil war in which military leaders on all sides are thugs.

Early on, the United Nations locked in Serbian military superiority with an arms embargo. Then U.N. diplomacy helped legitimize Serbian gains. The United Nation’s “Vance Plan� put Serb occupation forces in Croatia in the stronger bargaining position. As the war began in Bosnia, Serb leaders replicated those benefits, manipulating the U.N. negotiating process to gain maximum time for battlefield success.

But by the middle of 1993 the United Nations, in effect, changed sides. Its defense of Muslim positions bought the Muslim military time to regroup and discover new sources of arms. The Muslims began to believe that with a U.N. shield they could fight a long-term war of liberation. The United Nations, however, strives for neutrality--recently, for example, it threatened Muslim forces on the offensive in central Bosnia. Its actions lead each side, not unreasonably, to expect to continue using the U.N. presence to advantage.

The West had a choice to end the war on its terms. “Lift and strike� originally intended not merely to fight, but fight and win. The best interventionist alternative to “war-winning� was Gen. Bill Odom’s “war-ending� strategy, which required hundreds of thousands of additional Western troops in Bosnia. Less costly, a “stalemate� strategy, similar to the proposal from the so-called Contact Group (Russia, France, Germany, Britain and the United States), requires tens of thousands of troops to police a cease-fire.

NATO won’t, however, launch an air war to save Bosnia. Neither Bill Clinton nor Congress would tolerate U.S. troops in Bosnia. If there are no Americans, the Europeans won’t send more of theirs. “War-winning,� “war-ending� and the “stalemate� are no longer viable policy options in Bosnia.

The popular alternative in the United States, lifting the arms embargo, seems easy. No casualties, no political fallout. And it seems moral. Embargo lifters, however, offer no index for success other than the claim of “doing what’s right.� That philosophy hardly qualifies as a policy, but lifting isn’t even a choice. Once a trickle, smuggled arms are now a flood. U.N. muddling just slows down a de facto lifting of the embargo, except that the United Nations pays in lives for its delayed withdrawal.

We can expect a war of attrition where no side wins. The sooner the combatants realize they can’t rely on outside support, the sooner they could accept compromise.

We should ask ourselves the question European governments must answer: At what point does pressure from an arms buildup force the United Nations out? The West could either declare defeat and go home early in an orderly fashion or late, pushed out in disorder. Before this winter, the United Nations could depart relatively smoothly; during a winter of civilian hardship, withdrawal would be a huge public embarrassment. Spring puts the United Nations in a heavy cross-fire. Withdrawal then risks turning into a rout.

If the West is honest about its limitations, the reasonable remaining policy questions have to do with institutions. A salvage priority with an eye to serious future institutional reform--we don’t want to repeat this experience, but somewhere we will want to intervene again--argues for pullout sooner than later. From the ex-Yugoslav’s perspective--no matter how hard--Muslims and Croats will have to accept that Serb interests, despite repugnant Serb behavior, must be considered. And vice versa. Someday, accommodation will take place.