This strips away the last vestiges of our moral superiority in occupying Iraq

Those close to him mutter, under their breath of course, that Tony Blair's only moment of doubt over Iraq came in the wake of the exposure of the Abu Ghraib scandal.

Those close to him mutter, under their breath of course, that Tony Blair's only moment of doubt over Iraq came in the wake of the exposure of the Abu Ghraib scandal.

This is plausible, as our Prime Minister possesses a Gladstonian moral imperative. He believes that any economy with the truth over the threat from Saddam's vanishing weapons of mass disappearance would be forgiven in the short run by his electorate and in the long run by his Maker so long as he could convince both that it was done from the best of moral motives. Those shameful pictures of Iraqis hooded, naked, with electrodes strapped to their genitals, were devastating precisely because they demolished any pretension that the occupation could be justified by the moral superiority of the occupiers.

His doubts appear to have vanished by the time Tony Blair departed for his break after telling his party that he had come through the fire. How ironic, then, that he should return to be haunted by the ghost of Abu Ghraib in the form of not one but two US reports. Wednesday's report by General Fay concluded that culpability for the abuse could not be limited to the few bad apples so far charged. Suddenly the possible charge sheet has lengthened from half a dozen to half a hundred.

Part of the force of the Fay report derives from the manifest disgust of the career officers at what they discovered, including rape, beatings - in one case to death - and stripping of prisoners who were left naked in freezing cells. The practice which caused greatest revulsion to its authors was the use of dogs in a game to see which handler could first frighten an inmate into defecating on himself. With savage irony, these inventive examples of sadism were visited on Iraqis by coalition troops in the same Abu Ghraib fortress that had been a symbol of the brutality of Saddam.

But the most significant feature of their report is that the great majority of those they identify as conducting abuse were not simply guards but military intelligence agents. The reservists already charged have always claimed that they were carrying out orders to soften up detainees for interrogation. Sure enough General Fay found that in a majority of the incidents, military intelligence soldiers either solicited the torment or participated in it themselves. At this point it becomes impossible to sustain the pretext that the brutality in Abu Ghraib was the result of isolated sadism and not the product of a systemic policy.

The Director of Operations of the Red Cross, which first revealed the Abu Ghraib scandal, was blunt that "we are dealing with a broad pattern, not individual acts''. It was a pattern not only set at Abu Ghraib, but from Guantanamo to the US base at Bagram in Afghanistan. At all three centres around the globe, the same techniques have been exposed of hooding, sleep deprivation and sexual humiliation. It is simply not credible that a handful of reservists from the Appalachians happen to come across these practices on the internet. Somebody brought to Iraq the techniques that had been honed elsewhere.

The person who did visit Baghdad before the abuses broke out at Abu Ghraib was General Geoffrey Miller, the commander of Guantanamo. The Schlesinger report, also released this week, confirms that General Miller brought with him Rumsfeld's policy guidelines for Guantanamo and recommended them as a possible model for interrogation at Abu Ghraib. It was also General Miller who advised that dogs be used within the prison.

Nor did General Miller travel to Baghdad on a freelance initiative. He was instructed to go there by Stephen Cambone, a political appointment who had recently been chosen by Rumsfeld for the new post of Under-Secretary for Intelligence. At the time, the UN headquarters had just been bombed and the Pentagon was confronted with a widespread uncertainty which it had failed to predict and for which it had done nothing to prepare.

In short, General Miller took to Abu Ghraib techniques of interrogation approved by Rumsfeld at the specific request of Rumsfeld's junior minister. When the practices at Abu Ghraib burst upon an appalled world, it was General Miller, of all people, who was ordered back to take charge of Abu Ghraib. His arrival was presented as a mission to clean up the detention centres, but in reality his priority must have been to contain the political fallout from a scandal for which the chain of responsibility runs all the way up to the top of the Bush administration.

This responsibility is based on more than the embarrassing evidence that the politicians approved the techniques applied by the military. It is also a product of the culture of impunity which was encouraged from the highest levels. George Bush himself issued a presidential instruction that the Geneva conventions did not apply in the war against terror, and that those detained were to be denied the rights of prisoners of war. At his request, the Department of Justice submitted an opinion that mental torment and physical suffering inflicted as a by-product of interrogation did not constitute torture in the meaning of international law, which allegedly required an act to be specifically intended for the purpose of causing pain.

To their credit, the generals who prepared the Fay report were having none of this casuistry on what constitutes torture. Nor would any common-sense layman disagree with them. The practices authorised by Rumsfeld as approved techniques of interrogation, and therefore not by definition torture, include stress positions for prolonged periods, hooding, solitary confinement, and "exploiting individual phobias, eg dogs''.

Rumsfeld's rules of interrogation presumed that the detainees were guilty and assumed that they had information worth extracting. In fact the Red Cross estimate that 70 per cent to 90 per cent of the detainees at Abu Ghraib were wholly innocent of any connection with terrorism. The revelation of the practices visited upon them by the night shift may have come as a shock in the West, but they were already well known throughout the Sunni community of Iraq, many of whose extended families had members who had returned with harrowing tales of their experience. Abu Ghraib almost certainly fed the resentment that sustained the insurgency at a far greater rate than it produced any useful intelligence to combat it.

The techniques of interrogation employed at Abu Ghraib were specifically designed to exploit Arab culture and sexual taboos to inflict maximum humiliation and shame. Astonishingly, it never appears to have occurred to anyone in a chain of command that, for this very reason, the same practices would generate maximum hostility to the West when they became known across the Arab world.

The Schlesinger report concludes by lamenting the damage which Abu Ghraib has done to the image of the US among populations whose support it needs against terrorism. It is a damage that will continue so long as the Bush administration pins the blame on a few guards and dodges its own responsibility for the scandal.