Britain's worst intelligence failure, and Lord Butler says no one is to blame

What a shame that Anthony Eden did not have a Butler around to explain he was not responsible for Suez

What a wonderful specimen of the British establishment is Lord Butler of Brockwell. Urbane, unflappable and understanding. He should be put on display somewhere as a prize example of our ruling classes. Possibly the Victoria and Albert Museum would provide the right grandeur and period ambiance.

What a wonderful specimen of the British establishment is Lord Butler of Brockwell. Urbane, unflappable and understanding. He should be put on display somewhere as a prize example of our ruling classes. Possibly the Victoria and Albert Museum would provide the right grandeur and period ambiance.

There is an emotional disconnect between his measured tones and the brutal reality of the topic he was examining. The events on which he was reporting were the origins of a real war. In its carnage between 10 and 30 thousand people were killed, some of them blown apart by the largest bombs yet made from conventional explosive. For some death would have been mercifully swift. For others the end would have been agonisingly slow and death welcomed as a release from unbearable pain.

Yesterday Lord Butler calmly pronounced the intelligence on which the war was launched as hopelessly overheated. His conclusions on this point are so irrefutable that even Tony Blair had to admit that Saddam did not have any WMD ready for use. Lord Butler found that intelligence was often second-hand and, in the case of one "dominant" stream of intelligence, came from "a sub-sub-source". The absence of first-hand information meant most "intelligence reports" were in reality "inferential". The inaccuracy of the raw intelligence was then compounded by the exaggeration of analysts which resulted in "worst-case estimates, shorn of their caveats, becoming the 'prevailing wisdom'."

After the Butler report, it is embarrassingly clear that Parliament was misled into voting for war on the basis of unreliable sources and overheated analysis, producing between them false intelligence.

This must be the most embarrassing failure in the history of British intelligence. Yet according to Lord Butler, no one is to blame. Everyone behaved perfectly properly and nobody made a mistake. Poor things, they were let down by the system and institutional weaknesses. John Scarlett gets his very own specially printed Get Out of Jail Free card.

It used to be a standard mantra of Tony Blair's speeches that "responsibility and rights" are indissolubly linked. It turns out that responsibility is for job-seekers and single parents, not for our ruling classes. Lord Butler has produced elegantly crafted paragraphs explaining that none of them need take responsibility for the biggest blunder in British foreign and security policy since Suez. What a shame that at the time Anthony Eden did not have a Lord Butler around to explain he was not responsible for his decision to invade.

A good example of how the Butler style can magic away blame comes in his discussion of the phantom mobile laboratories, which formed the centrepiece of Colin Powell's presentation to the Security Council. Lord Butler is obliged to report that "no evidence has been found to support the existence of the mobile facilities." However this does not mean anything so crude as that the intelligence agencies got it wrong. No, "the conclusion must be that the main grounds for the assessment no longer exist." As Nixon might have put it, that intelligence is now inoperative.

Lord Butler was caught off guard by one journalist yesterday and confessed he was "surprised" that there was no reassessment of the intelligence as it emerged that the UN weapon inspectors could not find anything. A less phlegmatic man might have been astounded.

In his statement to the Commons, Tony Blair stressed the sincerity with which he believed at the time in the September dossier. I do not doubt him. But I do doubt whether he still believed it when he asked Parliament to vote for war six months later. In the intervening period he had received three further assessments warning him that intelligence on weapons of mass destruction was "inconsistent" and "sparse". He knew that the Joint Intelligence Committee believed that Saddam had dismantled his chemical weapons and dispersed them to different locations, with the result that they could not possibly be fired in 45 minutes. In his speech to the Commons on the eve of war, Tony Blair did not repeat a single one of the more lurid claims of the September dossier, largely, I suspect, because he had been warned by then they were unreliable.

Yesterday Tony Blair insisted that the absence of any threat from Saddam did not mean that there was no justification for the war. Perhaps. But it certainly means that there was no urgent necessity for war. We could have found the time, at no risk to ourselves, to let Hans Blix finish his inspections and confirm that Saddam had no weapons of mass destruction. I fear that for Bush and Blair, the real reason why invasion was urgent was the growing realisation that Hans Blix was about to remove their principal pretext for war.

Unfortunately for Tony Blair, the Butler report does not offer him much comfort on any of the other justifications for going to war. It concludes that there was "no evidence of co-operation" with al-Qa'ida. Worse, it reveals that the Joint Intelligence Committee warned that occupation would result in coalition forces being attacked by terrorists.

Far from being a victory over terrorism, the war on Iraq has been a spectacular own goal. We have created precisely the conditions in Iraq in which al-Qa'ida can thrive - poor security, open borders, and a population with a grievance. The heavy-handed military operations by US forces and the scandal of the Abu Ghraib abuses have presented the recruiting sergeants and fundraisers for Osama bin Laden with a propaganda gift.

Tony Blair needed a catharsis if he was to put the controversy of Iraq behind him. Yet by pretending that all is well and everybody did their best, first Hutton and now Butler have denied him any opportunity for catharsis. Yesterday the Prime Minister should have been admitting that there were serious mistakes, that lessons had been learnt and that, above all, it will never happen again.

Anyone listening to him in the Chamber could not have left with anything other than the impression that he is absolutely convinced he was right and that he would do it all over again in precisely the same circumstances. Notably there was no commitment to the more formal, collective style of Cabinet government for which Butler called, and I do not imagine any of its ministers are holding their breath expecting dramatic change.

The irony is that the only ministers who have left the Government over the chapter of errors that led us into war in Iraq are those who could not support the war, and the only people to be sacked are those at the BBC and the Daily Mirror who criticised it. Everyone who contributed to the errors of judgement is still in post and now patted on the head by Lord Butler for doing the best they could.

That may seem very British and very sensible to Lord Butler. To the rest of the world it will seem barmy.