Leading Article: Nato's victory will be complete when the Kosovars return

IT IS a victory that does not feel particularly victorious. We cannot yet be sure that Slobodan Milosevic will keep his word. But even if he does, and the Serb tanks and troop-carriers start rolling out of Kosovo, any sense of satisfaction will be tempered by the sorrow that so many had to suffer so much. And even if the refugees begin to reclaim their land and their homes, the scale of the task of reconstruction will darken the celebrations. Nevertheless, if Milosevic pulls out of Kosovo it will be a victory for Nato and, after it, many things will not be the same again.

The new Nato will have had a baptism of fire, in its first "hot" conflict since the end of the Cold War. Its three new members, Hungary, Poland and the Czech Republic, joined just days before the bombs started falling on Belgrade. They joined an organisation that has just found a role. "Nato's success in Kosovo will be the biggest deterrent to tyrants the world over, and the biggest rallying call for democracy," as Tony Blair said in Bulgaria last month.

Victory for Nato should also put an end to the thoughtless assertion that "wars cannot be won from the air". Nato's campaign was far from perfect, in its conception and execution. But a ground invasion of Kosovo may now turn out to be unnecessary. This newspaper consistently called for the deployment of ground troops to be threatened - and to make the threat credible, Nato would have had to be prepared to go through with it. In effect, that is what happened: the prospect of 50,000 Nato troops on the borders may well have concentrated Milosevic's mind.

The biggest mistake of the war, then, was the brief ruling out of ground forces early on. It may have prolonged the bombing by letting Milosevic doubt Nato's resolve. But it was not a catastrophic error; ground forces could never have been deployed right at the start - at that time, there were only a few thousand Nato troops stationed in Albania and Macedonia, without any of the support they would have needed to fight 40,000 Yugoslav soldiers in Kosovo. The troop build-up should have begun much earlier, but until Milosevic had repeatedly broken undertakings to abide by United Nations resolutions, it would have been impossible to mobilise support in other Nato countries for such aggressive preparations.

Of course, most of the refugees were made homeless after Nato began the bombing. But 300,000 had already left Kosovo, and military action was the only way to ensure that, as Mr Blair again said in Bulgaria, "the policy of brutal savagery that is `ethnic cleansing' must fail, and be seen to fail".

Peace deal or no, it is worth devoting some thought to the immense challenges that will follow the war. First, it should be restated that Nato has no quarrel with the Yugoslav people; it will be time to start building bridges, metaphorical as well as real. That is why the Irish government should reconsider its ban on the football match between the Irish and Yugoslav teams. Secondly, the Kosovo Liberation Army will have to be controlled, and prevented from launching reprisals on the Serb minority in Kosovo. Thirdly, Milosevic will still be in power in Belgrade. He will not be able to leave his rump Yugoslavia, for fear of arrest to face trial for crimes against humanity, but he will still be there, and Nato will have to guarantee the rights and autonomy of Montenegro and Vojvodina - the remaining two ethnically mixed parts of Yugoslavia.

Milosevic's acceptance of Nato's terms is only the end of the beginning. But that is the important bit. That is the bit that is about good and evil, as Mr Blair said. The rest is administration. If this is peace in the Balkans, Mr Blair's sometimes rather lonely stand will be vindicated. There was a heavy price to pay, but it was worth paying, and if Milosevic's policy of "ethnic cleansing" really has been defeated, we should give thanks.