Gamble that Nato cannot afford to lose

A CAUTIOUS cheer: but if things go wrong, then within a fortnight British soldiers might be at war in Bosnia. If the Nato air attacks round Sarajevo go ahead and provoke Serbian retaliation against British troops or aid workers, then the Army and the Serbian guerrillas will quickly become locked in combat. Big ifs, but not implausible ones. What then? The best brains in Whitehall are racking themselves. And, er, they don't yet know.

This is worth dwelling on. Consider: Britain and her allies are engaged on a course of action that could turn her troops from heavily armed aid workers into fighters. And yet, only days away from the deadline, there is little sign of any grand plan. 'We don't want to fight, but by jingo if we do, We're not entirely sure, whether we'll carry it through . . .' Well, at least it rhymes. Why this nervy sabre-rattling? Because a Serbian mortar crew got lucky. Had the Serbian soldiers behaved sensibly and carried on just blowing apart two or three small children a day, contenting themselves with a moderate and humane rate of decapitations and maimings, then there would have been no problem. Western television viewers have become hardened to shots of white-faced Sarajevans being operated on without anaesthetic. But Milovan and Zarco felt greedy last Saturday, just couldn't help themselves, copped too many in one go. And here we are.

It is right to recall that the Serbs deny the massacre, explaining it as a Muslim conspiracy to kill their own people in such numbers as to draw the West into the war. In this murderous Balkan struggle, any depth of wickedness is possible. But the Serbs have lied too often.

Still, whatever combination of television, Western politics and high explosive provoked it, this is clearly an important moment in the history of the Bosnian war, and of Nato. Despite huge risks ahead, a little optimism is justified. It would be bad politics for the Serbs not to withdraw their artillery. They have judged the weakness of the West pretty shrewdly up to now and must realise that there is some danger of Nato meaning it this time.

Perverse though it may be, a Serbian withdrawal would also put political pressure on the Bosnian government, since it would strengthen the position of the European governments trying to broker a peace deal. On the ground around Sarajevo, the infantry-strong Bosnian army would probably try to use the absence of Serbian artillery to retake territory. Nato and the European Union would then have to put pressure on them in order to preserve the ceasefire. Some head-knocking would follow all round. This might be what is required to conclude the peace deal in Geneva. At any rate, the first indications are good. But still, the danger is that the Serbs will decide to act militarily, not politically, and call the Nato bluff. No one really knows how much damage air strikes would do. But if the Serbs were determined to confront the West, then they would be almost obliged to retaliate, calculating that enough British, French and Canadian deaths would push the UN out of the war, and allow them to finish Sarajevo off.

It would be perilous to attack British troops directly - they are well armed, well positioned and well led. When attacked, they are not only allowed to fight back but also to call up air power in support. But civilians, and other UN troops, are easier meat. The Serbs would then assume that after some huffing, the blue berets would scarper. The ultimatum designed to protect Sarajevo would result in Sarajevo being left open to her enemies.

In the end, the Serbs still have a real political and strategic choice to make. If they want to do a deal in Geneva and see the sanctions ended, they will bow to the ultimatum and watch the pressure build up also on the Bosnian government. If they want a full-scale military victory, they can try to push the West out of the Balkans this spring. So we come back to the main question, with which the relevant ministries and civil servants are struggling: in the end, would we fight?

Although every minister has so far answered no, the real answer may be yes. Not because of a mortar attack, but because of the growing realisation in Nato that this has become a geo-political issue. This small but deadly game of bluff and counter-bluff around a shattered Balkan city is one whose outcome matters to the security of all the Western countries involved. With the collapse of empire, we have mostly lost the ability to see that the relationships of great powers can turn on small events - the security of dusty frontier towns, or tribal conflicts far away. But it is so.

Quite a lot of the world is wondering whether the European Unionists and the Nato-ites any longer have the will to fight to uphold their religion, which they call variously international law and democracy. Any even a half-attentive observer of the Bosnian war will have guessed long ago that the answer is no. That answer has implications for the Baltic states, for Ukraine, for the rest of the Balkans. And, eventually, for the West Europeans themselves.

Now there is a last chance to correct that impression, and Nato has decided, however belatedly, that self-preservation as well as decency requires that chance to be taken. But this is one heck of a gamble: Nato is playing not only with lives or with honour but also with its future. If the Serbs refuse to withdraw and if, after a few exchanges of gunfire, all those white-painted war machines are loaded up and shipped back home, then the whole Western security system will be in a state of acute crisis, humbled, divided, voiceless.

The alternative, which is to be ready to lose soldiers in combat within weeks, in a conflict which is complex and where we have no clear objectives, is unpleasant and dangerous. There is only one thing to be said for it: it is now more dangerous to lose our nerve and scarper.