Leading Article: Bosnia's best hope

HERE is what a realist might say about the growing pressure on Western governments to intervene with arms in Bosnia. First, think very hard about what you intend to achieve, both in the short and the long term. Would armed intervention merely seek to protect the Muslims, ensure them access to humanitarian aid and halt the advance on what remains of their territory? Or would it intervene on behalf of the state of Bosnia itself, which much of the world (including Britain) recognised earlier this year, to drive back the Serbs and the Croats and restore Bosnia's old territorial integrity? Both options would probably mean lost lives and that may be too high a price for any Western government. And, wars being wars, the first option could well lead to the second. In which case, your realist might shout, don't dream of it. The war in Bosnia is not a simple case of invaders versus the invaded. It is also a civil war, reflecting the complex reality and ambitions of the different communities who happen to share a state the world may have been too quick to recognise. 'Ethnic cleansing' has drastically changed the proportions since the war broke out in April, but before that date Muslims comprised 44 per cent of the population, Serbs 32 per cent, Croats 17 per cent. Today Serbs hold about 70 per cent of Bosnia's territory and that part under Croatian control has been de facto annexed to Croatia.

That, today, is the position on the ground. Realists - perhaps the British government among them - would argue that it is best to acknowledge it: redraw the map of Bosnia, give this big bit to Serbia, that smaller bit to Croatia, and the rest to the Bosnian Muslims. True, aggression will have been rewarded, the 'ethnic-cleansers' will go unpunished, and thousands of Muslims will never see their homes again, but that is the way of the world. Some problems do not have solutions, at least in the short-term; look at Northern Ireland, the Punjab, the West Bank, Kashmir.

The trouble with realism, however, is that it does nothing to stop the terrible events that occur, day on day and night by night, in Bosnia. Apart from the thousands of civilian casualties, dozens of United Nations peacekeepers and European Community observers have been killed and wounded there. Humanitarian workers risk their lives daily. In Bosnia, we have reached the point where the risk of doing nothing outweighs the risk of action. That is why Washington is right to push for enforcement of the 'no-fly zone'. It may look meaningless: the Serbs have flown no combat missions in Bosnia for two months, and their air force is in no condition to take on the West's war planes. But the purpose of enforcement will be to prevent Serbia from ferrying military supplies, fuel and food by helicopter to the Bosnian Serbs. By sealing off this route, the West will help to isolate the Bosnian Serbs and make them more likely to sue for a settlement.

The military position of the Bosnian Serbs is much weaker than is generally understood in the West. They made their territorial gains in April, the first month of the war, when terror and surprise brought swift results. Since then, the war has not gone so smoothly for them. And worse may lie ahead. So far from wanting to expand the war into Kosovo and Macedonia, the generals in Belgrade are extremely alarmed that they may soon face a conflict on three fronts: Bosnia, the south, and eastern Croatia, where Croats are determined to reconquer land lost to the Serbs last year. This means that now, of all times, is not the moment for the West to offer the Serbs (or the Croats) a slice of Bosnian territory in exchange for ending the war.

Over the past two years, the West has not covered itself in glory with its Yugoslav policies. Lord Owen and Cyrus Vance, the co- chairmen of the international conference on Yugoslavia, have gone some way to repairing the damage. Now the West has a chance to build on their efforts, and it should start by the strict enforcement of the no-fly zone in Bosnia. It carries risks; all the options do. But, realistically, it is the best hope.