The harrowing sight of Sergeant George Long struggling to escape his armoured vehicle with his face and back on fire lives in our minds. The events in Basra represent another stage in our loss of innocence about the Iraq war. Until last week it was possible to believe that British forces, operating far from Baghdad and the Sunni triangle, were relatively safe.

We liked to believe that that was due to our soldiers’ superior mode of operations. While American forces roared through the streets of the capital in heavily armoured convoys, our soldiers’ friendly faces looked out from open-topped vehicles. Whereas GIs shot from the hip, British troops engaged the Iraqis’ hearts and minds.

Such illusions are shattered. Nearly 100 British soldiers have died since the war began. Toby Dodge of Queen Mary College, University of London, believes that the “softly, softly” approach was dictated not by tactics but military weakness. Britain simply does not have enough troops to police the vast area under our authority (even with Italian and Australian help). Our army has been forced to do something forbidden in military textbooks: to keep the peace among a population that we were unable to disarm.

So we are failing. Basra has seen 120 assassinations this year. Kidnappings are common. Insurgents have wounded and murdered students at Basra University with impunity.

I criticise neither our soldiers nor their officers. Long’s heroism in remaining in the field for hours after receiving serious burns is further evidence of their courage. I need no convincing that they have done a magnificent job.

However, their task is impossible. They are asked to oversee the maintenance of order in a convoluted struggle between rival groups vying for power. It might be done with effective local help. But the Iraqi security forces were disbanded. Of those who have been trained since, some are good, but many are poorly led and incompetent. They have been infiltrated by the militias, as Mowaffaq al-Rubaie, Iraq’s national security adviser, admits.

When Colonel Bill Dunham, an army spokesman, was asked on the radio whether our forces could go on holding the ring, he refused to comment. His reticence was understandable. The warring factions have only one thing in common: a detestation of the occupying alliance, represented in southern Iraq by Britain.

British commanders understand fully the range of forces opposing them. We face attack from Shi’ite militants — the Mahdi army, controlled by Moqtada al-Sadr, the cleric, and forces led by Abu Mustafa al-Sheibani, probably backed by Iran.

There is no sign that the politicians directing the operation from afar appreciate such intricacies. Washington and London issue platitudes rather than analysis. There is a gulf between how things are perceived on the ground and how they are glossed over in the capitals.

Former army officers who I meet socially generally express their opposition to Britain’s adventure in Iraq. Last week Field Marshal Lord Bramall, a former chief of the defence staff, and General Sir Michael Rose, a one-time commander of our operations in Bosnia, spoke out publicly. I imagine that many serving officers share those doubts.

These are difficult times for people like me who backed the war. Many of the arguments that we put forward have lost their force. We liked to say that however bad things were, they were worse under Saddam Hussein. It seemed a safe claim after his reign of terror. But perhaps 100,000 Iraqis have died since liberation. Does the average Iraqi citizen feel more secure now? Hundreds daily seek work by joining the queues in the open air. They must be desperate to offer themselves as such obvious targets for suicide bombers.

We imagined that Iraqis would benefit from cleaner water, more reliable electricity and better education. But America, the land of plenty, has failed to supply creature comforts to Iraqis, just as America, the superpower, has failed to keep them safe.

I have not become an admirer of those who opposed the war. For some of them, disagreeing with every intervention since Bosnia was a matter of routine. Others merely detest anything linked to George W Bush. I have not heard any of them grapple seriously with the problem that the West faced in 2001. The 9/11 attacks made us look weak. After previous outrages we had been irresolute and appeared unwilling to defend ourselves. United Nations sanctions were collapsing. Saddam’s long and successful defiance of the West added to Al-Qaeda’s contempt and so to our danger.

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