Rupert Cornwell: Bush presidency looks vulnerable amid chaos of Iraq and parallels with Vietnam

It was the neo-conservatives' magic solution: an invasion of Iraq that would rid the world of the odious Saddam Hussein, sow the seeds of democracy in the heart of the Arab world and hasten the day when Israelis and Palestinians lay down like lion and lamb in peace together.

Little more than five months since American troops and their British allies rolled north across the Kuwaiti border, those overblown ambitions lie close to ruin. Iraq is theatre to a guerrilla war that the mightiest military power in history cannot suppress. In fact, it can't even ensure the supply of water and electricity to the country's ever more exasperated population.

As for the road-map to peace in the Middle East, the prescribed path is heading over the edge of a cliff. A seven-week ceasefire has ended as others before it, in the usual grisly mix of Palestinian suicide bombings and deadly retaliatory attacks against the militants by the Israelis.

In Washington, a President facing re-election barely 12 months hence issues the ritual condemnations of terrorism and vows the United States will not be deflected. But exceedingly tough choices are fast approaching, amid parallels with America's foreign disaster in Vietnam that, however inexact, can no longer be ignored.

Now, as in the 1960s, the debate is whether to send in more troops. In Vietnam such a decision led the US deeper into a morass; in Iraq today, a substantial increase in the American force ­ currently some 140,000 supplemented by 20,000 soldiers from Britain and other supporters ­ is being presented as the one sure way of suppressing the guerrilla resistance and guaranteeing basic public order and public services.

Estimates vary: some say 30,000 to 40,000 additional soldiers will do the trick; others extrapolate from the occupying forces that have presided (on the whole successfully) in Bosnia and Kosovo and talk Vietnam-sized numbers of 300,000 to 500,000 men for the total force. The former was the figure roughly alluded to by the former army chief of staff General Eric Shinseki before the war, for which he was publicly rebuked by his boss Donald Rumsfeld, the Secretary of Defence.

Mr Rumsfeld still refuses to budge, telling Time magazine that the US has "adequate forces" in Iraq. This stance reflects political reality: the last thing Mr Bush wants is a surge in war costs, already running at $4bn (£2.5bn) a month, as the economy stagnates and his opinion poll ratings slide.

It also reflects a military reality: does the US, whose forces are almost as globally stretched as their British counterparts, have the men available out of a total 490,000 personnel on active duty? And if not, should it (again shades of Vietnam) reinstate the draft?

Nonsense, says Mr Rumsfeld, adamant as ever that the US armed forces need to be modernised, not enlarged. Of one thing, however, there is no argument: the utter failure of the Pentagon, lured by the siren calls of the neo-conservatives and its pet exiled Iraqi leader Ahmed Chalabi, to plan adequately for the postwar period.

In the meantime, American troops continue to die ­ two more of them over the weekend, raising the total US death toll since the war began on 20 March to 275. Of these fatalities, 138, almost exactly half, have been since 1 May, when President Bush declared an end to "major combat operations", 65 of them in a growing guerrilla war.

Each day sees a dozen or so attacks. But as occupying forces, American troops have a duty to protect Iraqi civilians as well as themselves. Major William Thurmond, the Allied spokesman in Baghdad, points out: "We can't indiscriminately use the firepower at our disposal."

In other words, the most sophisticated weaponry in the world is no substitute for professional peace-keepers, police and other specialists needed to rebuild countries. Not just the Pentagon but the entire Bush administration has been found wanting.

Britain was supposed to have an easier job in its command zone of southern Iraq, thanks to the region's long hostility to Saddam Hussein, and to the vaunted peace-keeping expertise of the British soldier.

Not so, however. Three British servicemen were killed and another seriously wounded in an attack on Saturday, bringing to 10 the victims of the guerrilla war since 1 May. The number of British dead on active service in Iraq now stands at 49 ­ higher than during the 1991 Gulf War, which left 47 dead.

"Clearly it is worrying. If anything, things are getting more difficult," says Stephen White, Assistant Chief Constable in the Police Service of Northern Ireland, who is in Basra to help the Iraqis develop a civilian police force. Bernard Jenkin, the Conservatives' defence spokesman, went further still, telling Sky News the Ministry of Defence might have to review its entire strategy in southern Iraq.

Other organisations have already done so. Correctly, Washington may claim that much of the country is calm, that a majority of the population supports what America is trying to do, and that only a tiny minority yearns for a return of Saddam's regime.

But enough of Iraq is so dangerous that the Red Cross announced yesterday that it was scaling down its humanitarian work, for fear that it would become a target for attack like the United Nations, whose top official in Iraq, Sergio Vieira De Mello, was among the 24 people killed in last week's truck bombing at the UN's Baghdad headquarters.

The decision was "heartbreaking", a Red Cross official said, but the threats against it had to be taken seriously. More important, other relief organisations are likely to follow its lead, reducing aid for ordinary Iraqis when they need it more than ever, and only fuelling anti-American resentment.

But the Bush administration faces an equally difficult, if different dilemma. Clearly the US cannot cut and run, at least not in Iraq. But American public opinion is becoming ever more dubious about enterprises that Washington seems unable to accomplish on its own. As he must, Mr Bush insists that America will "stay the course". But pressure is building on several fronts.

With his Middle East plan in virtual ruins, can the administration prevent Ariel Sharon, Israeli Prime Minister, going all-out for a "military victory" over the radicals ­ a victory that history teaches would solve nothing?

The crux, though, is Iraq. Sooner or later, and probably sooner, the President must explain to Americans exactly how he intends to achieve his goals in Iraq. And this leads to the question of the role of the UN, the organisation that Washington disdained in the run-up to the war. More forces are needed but, increasingly plainly, the countries that can provide the skilled troops and personnel are those such as France and Germany, which opposed the war. They understandably insist on formal Security Council approval and a central decision-making role for the United Nations.

But for Mr Bush to grant this would be an implicit admission that he was mistaken in believing the US could go it alone, an admission that would be seized on by Democrats before the 2004 election.

For a man disdainful of multilateralism, and who prides himself on being a macho, no-nonsense Texan, it would also be akin to a humiliation.

Not surprisingly, even Colin Powell, who last week even appealed to that Bush administration pariah Yasser Arafat to use his influence to calm Palestinian passions, continues to insist that any wider involvement by the world body must leave overall US control intact.

The UN is not a power like the medieval papacy. But if the Iraq morass deepens, even this president may have no choice. Like the German emperor Henry IV at Canossa in 1077, doing penance before a pope he had sought to depose, Mr Bush may have to turn for help to an institution he once insulted.