IT TOOK IMMENSE effort to combat the evils of Serbian "ethnic cleansing" to permit the return of Kosovar Albanians whom Slobodan Milosevic had rounded up and expelled. Kosovo stands now as a test case of the merits of military intervention to defend human rights. Just in the past few weeks, the United Nations has issued abject apologies for its failure, in Rwanda and Bosnia, to devote sufficient resources to prevent bloodshed. Yet once again, this time in Kosovo, the United Nations is falling short, and innocent Serb civilians are being killed.

In fact, the United Nations as an institution is doing all it can. Its member nations are falling short, from Argentina -- which promised to provide 80 policemen but has furnished only 38 -- to Zimbabwe, which has furnished 24 of a promised 55. Altogether, the United Nations initially planned an international force of 6,000 policemen to help restore order and protect minorities in Kosovo. Due to feeble international response, it had to scale down its planned deployment to 4,000. So far, countries have sent only 1,800 -- a "scandal," says Bernard Kouchner, the U.N. administrator in Kosovo.

The broken promises are part of a larger syndrome of forgetfulness and unrealistic expectations. In the United States, a surreal debate rages over whether Serb forces murdered 10,000 Kosovar civilians or "only" 6,000 or 4,000 or 2,000 -- as if the lower number would excuse everything. People complain that Serbs and Kosovars will not live in harmony, as if the nightmare of this year -- this year, not even 12 months ago -- did not happen. There seems to be a desire to forget that Serbs forced an entire nation from its homes, raped women, poisoned wells, forced men into basements to be burned to death. There is a kind of amnesia about the thousands of Kosovar civilians who remain unjustly imprisoned inside Serbia -- and about the ultimate architect of these war crimes, who remains comfortably ensconced in power in Belgrade.

This is not to excuse the revenge killings carried out since the war by elements of the Kosovo Liberation Army -- far from it. Extremists within the Albanian community endanger not only Serb civilians who have chosen to remain in Kosovo but also Kosovo's chances of being accepted into the international community as some kind of sovereign entity. Most Kosovo Albanians seem to understand this; polls show support for nonviolent leaders. Most people do not want more killing.

But the wishes of the majority alone cannot stop crime. Nor can U.S., German and other NATO troops, who are not trained or equipped to prevent or investigate murder. For that, Kosovo needs a police force: a local one, such as the United Nations is now beginning to train, and an international one, to fill a void until the local police are ready. By stinting on the relatively modest contributions of money and personnel needed, U.N. member nations are risking Kosovo's chances to achieve peace, democracy and reconciliation. "Scandal" is too mild a word.