Peace will come to the Middle East only if Mr Bush decides to impose a solution

War highlights weakness. This may not apply to hardware, but the Americans have still not overcome the risk-averse mentality which has dogged them since they lost the Vietnam War; the fear that public opinion might desert their leaders if the butcher's bill is too high.

But the real American problem is geo-political. The basic deficiencies in the American world-view have not yet been addressed. They arise from the United States' reluctance to embrace its responsibilities. Over the past few days, protesters throughout the world have been denouncing Yankee imperialism. In many countries, the political leaders covertly agree with the demonstrators. If only they were right.

The problem does not arise from American imperialism, but from its absence. In Afghanistan, in Iraq, and in dealing with al-Qa'ida, the Americans' mindset is essentially defensive. They have set out to strike back at those who struck at them on September 11, or who might do so in the future. They have not yet understood that defensiveness is not enough.

This might appear to be contradicted by the often-expressed American desire for a new order in the Middle East: not so. The US may will the new order, but it refuses to will the means to bring it into being. Instead, there is a naive belief in the universal panacea of democracy. If the Middle East is in chaos because most of its regimes lack legitimacy and oppress their peoples, then hey presto: give people the vote and they will elect better governments.

If only that were true. Throughout the region large numbers of people cannot wait to elect a worse government. In Iran and Iraq, democracy might act as penicillin. In Saudi Arabia, Egypt, Algeria and even Pakistan, it could turn out to be ricin. If the Americans want a new order, they will have to create one. That will require them to overcome their reluctance to embroil themselves in nation building.

In Iraq this may not be necessary. Though no one knows what will happen in the aftermath of an invasion, it is possible that the Iraqis themselves will work to create a better future. Yet even if Iraq did come right, there would be no reason to suppose that the same factors would operate in Saudi Arabia. Members of the Bush team occasionally sound as if they would be happy to see Saudi Arabia slide into crisis. But they would not be happy with the outcome.

Radical change is necessary in Saudi Arabia, without imperilling stability. In its initial phase, such reform could only be brought about by a strong-willed autocrat who could use the strengths of the existing system in order to help him to defy the De Tocqueville dictum that the most dangerous moment for a previously repressive regime is when it begins to liberalise. The Saudis need their own version of Ataturk. This Prince Ataturk, for he would almost certainly come from within the royal house, could not be a secularist like the great founder of modern Turkey. But he would need to create a new state, including a sizeable democratic component, while resisting the fanatics.

All that should have happened at least 10 years ago, so it may now be too late. There may no longer be any middle ground in Saudi Arabia between the endemic weakness of the House of Saud and the threat of the Wahabis, the fundamentalist sect which was the nursery of al-Qa'ida. But it is still worth trying. It is certainly better than mouthing platitudes about democracy while Saudi Arabia falls apart.

But there is an even bigger challenge than Saudi Arabia: Israel-Palestine. Here, President Bush's position is paradoxical. No previous President has talked so much about the need for a Palestinian state, yet no previous President has seemed so emotionally enthralled to Israel. His administration often appears to support Israel, right or wrong. This approach is based on a simple premise: that Israel, an ally menaced by terrorism, is a democracy which must be supported

That is an understandable reaction, but it makes one false assumption while leaving one question unanswered. The false assumption is that Israel is always the best judge of its own security; the unanswered question being what mechanism will bring a Palestinian state into being.

The Americans sometimes sound as if they believe that this too could come about through a mixture of spontaneity and democracy. If the Palestinians produced a decent leadership, the Israelis would immediately sit down to cut a deal. It is a wonderful idea, but there is as much chance of it happening as there is of flying pigs forming a guard of honour as the world's swords are beaten into ploughshares.

Far too many people on both sides are addicted to the sword, and are happy to postpone peace-making in the hope that events will move in their direction. General Sharon claims that he no longer thinks, as he once said, that there is no need for a Palestinian state because one already exists in Jordan. Does anyone believe that he would not still like to wake up one morning to be told that during the night, the Palestinian population of the West Bank had moved across to the east?

In recent years, Mr Arafat has more or less said that he now accepts the existence of the state of Israel. One does not have to be much of a cynic to doubt his sincerity and to suspect him of still hoping for some dramatic realignment of forces which would make the whole of Israel vulnerable.

There are plenty of moderate Israelis, and there are also Palestinian moderates, most of whom conceal their true views because of fears for their personal safety. But even if the moderates did gain power and started talking – an enormous if – they would be at the mercy of the blood-shedders. A suicide bomb, an Israeli reprisal; the whole cycle would have begun again. The depth of mutual suspicion and the strength of antagonistic forces would combine to sabotage the peacemakers.

Unless the Americans were to intervene and, in effect, impose a settlement. After all, everyone knows what that settlement must contain: an absolute guarantee of Israel's boundaries in exchange for a Palestinian state occupying virtually the same acreage as the pre-1967 West Bank and Gaza. The details would contain plenty of devil, especially on Jerusalem, but the shape of the overall package is clear. All that is lacking is a steamroller's momentum to compel both sides to accept the inevitable. This would not be easy to achieve. But an America with enhanced prestige from a successful war might just have a chance. It would require a mixture of fortitude, persistence, unlimited willpower – and luck.

It may be, however, that President Bush possesses those qualities, and he has one further attribute which gives a little ground for optimism. "Just about the least guileful President in American history'', as one of his aides once described him, this is a man who says what he means and means what he says.

He has said that he wants a peace deal, including a Palestinian state. So we now have to hope that he has the courage to try to bring that about. Nobody else could.