Iraq is a fatwa away from a guerrilla war - but the explosion can still be avoided

Iraqis see an army that is afraid of the people it says it wants to protect, praying only for the moment it can go home

The rubble in Mansoor has been there for several months. It was there when American troops first entered Baghdad. It has been there for the duration of the occupation. Anybody could wander up and look. If they wanted they could carry away bits of the broken masonry or the scattered personal effects. This was not a protected site. No more than the mass graves discovered in the south of Iraq or the prisons and intelligence offices ransacked under American eyes. But this week the rubble of the restaurant where Saddam might or might not have been killed was sealed off by the Americans. Suddenly it has become a place of importance.

Somewhere in the tangle of concrete and metal the US hopes to find the body - or pieces of the body - of Saddam Hussein. There are two frightening conclusion arising from this. The fact that it took the American military authorities months to begin a forensic investigation of such a site suggests appalling incompetence. Secondly, the fact that the US is now desperate to produce proof of the monster's demise points to just how perilous the occupation is becoming. The US needs to produce the body because enough Iraqis believe Saddam is alive. Why, you might ask, should this matter one way or another when America and Britain won the war?

Why should Saddam's life or death worry Iraqis? It matters because having won the military battle the peace is being frittered away. The chaos of the first week of occupation has been followed by weeks of bumbling and alienating tactics; the Iraqi people are losing what little confidence they had in their occupiers. They are frightened and confused. Others are bitterly resentful. What they see is what any visitor to Baghdad or other American-occupied towns can see: an army that is afraid of the people it says it wants to protect, an army that looks and often acts as if it has arrived in a spaceship, speaking a different language and praying only for the moment that it can go home.

I sensed it only too clearly in the first few weeks after the city fell. The troops told us again and again how they just wanted to go home. A marine in Tikrit who'd been in the Gulf for three months and in Iraq for two weeks told me: "I've been in this country too long." Too long? I didn't want to tell him what I thought - he and his buddies would be digging in for a lot longer, that this was a conflict that would keep America pre-occupied for years to come.

It was the same when you spoke to airborne and cavalry troops. They were mostly friendly and very open. But Iraq scared them. So when some freelance hooligan with a rifle fired a few shots at them, they opened up with devastating firepower. They may have killed the hooligan but usually a few other people were slaughtered as well. The local population naturally took a dim view of this. Very few of the units had Arabic interpreters and I don't know if this has improved very much. They still patrol the streets in full body armour with rifles at the ready. They do it because they need to, but why do they need to? It isn't because the mass of the population loves Saddam and hankers for his return. The overwhelming majority are delighted he is gone. But they were never going to love America for doing the job. The continuing presence of American troops on their streets is a reminder of their own failure.

Nobody ever trained these young men for the job of policing or rebuilding. They were sent to fight a war and were told it would be easy. It did turn out to be a relatively straightforward military campaign. But the overwhelming military might which secured the swift victory of April is ill-suited to navigating these dangerous months of summer. The ambushes on American troops in Faluja and in Balad were probably sponsored by elements close to the old regime. The gunmen are small in number and shouldn't represent a significant security threat. But you can bet the constituency of support for such groups - particularly in Faluja - is swollen every time an unarmed civilian is shot, every time the Americans kick down doors and drag away people for interrogation. To the Baathists who are staging attacks on US troops, a living Saddam is an inspiration. That is why the search in the rubble of Mansoor represents such a furious priority for the American military.

The Iraqis sense the Americans' fear. No society on earth is more acutely sensitive to the scent of fear than Iraq. That is why people in Baghdad have armed themselves to fight off looters. It is also why they place their faith in the mosque and the militias who do the bidding of the imams. By postponing the democratisation of Iraq, the American pro-consul, Paul Bremer, has deepened their alienation. What needed to happen was actually quite straightforward. First the US needed to deploy enough troops in Baghdad to stop looting and restore basic services. Next they needed to make it clear that they would talk to the genuine representatives of the Iraqi people, not the pet Iraqis imported from Washington.

More than anything it was the arrogance of Donald Rumsfeld which made his commanders' task so difficult from the start. The Defence Secretary thought peace could be done on the cheap. So there were never enough troops to secure Baghdad against the law-and-order catastrophe that followed the regime's fall. He also thought he could import the kind of Iraqis he likes and that the people would do his bidding and support these men. Now that it hasn't worked out and young Americans are dying in ambushes there is nervousness in Washington. Don't be deceived by the victory chants in Qatar earlier in the week. The intelligence flowing to the White House, and to Downing Street, is sobering. The British zone is quiet but only because it has been made privately clear to leaders in the south that Britain has no plans to sit on them permanently.

The country is armed to the teeth. The attacks in Faluja and elsewhere are but the smallest hint of what is to come if the Shia majority runs out of patience with the Americans. All that it needs is for religious leaders to order their followers to fight the US and the British and it will happen. We are a fatwa away from guerrilla war.

There is a way of avoiding the looming tragedy. If Mr Bremer can persuade the White House that peace is possible only by giving real power to the Iraqi people, there is hope. The Shia leaders in particular are shrewd enough to know they need American help to rebuild Iraq. They do not want to suffer the economic desolation and destabilisation that go with being America's sworn enemy. Mr Rumsfeld won't want to do this because it means giving power to clerics who terrify him. His choice is to wait until they decide to make Iraq ungovernable.

Every day that Rumsfeld and others try to avoid reality, the greater the chance of an explosion. It may be too late already. A friend who knows the place well came back yesterday and told me it was going to hell in a hand basket. I am not yet quite so pessimistic but it's a matter of degree. I realise I have gone through this whole column without once mentioning weapons of mass destruction. It might be because the threat of present calamity is so great.

The writer is a BBC Special Correspondent