Paul Vallely: Blair's glinting eye turns to Iran

A glimpse of the old messianic mission returned when the former prime minister appeared before Chilcot

Until the last 10 minutes, there was little drama in Tony Blair's testimony to the Chilcot inquiry into the lessons that should be learnt from the inglorious business of Britain's connivance in the American invasion of Iraq. But then one woman whispered a single sentence from a few feet behind the former prime minister.

Like most of the population, I made up my mind about Tony Blair long ago. What has emerged from the largely underwhelming inquiry set up by Gordon Brown when British troops finally left Basra in 2009 has only reinforced existing prejudices of Blair detractors and apologists. That was, presumably, why so many of those who Twittered through Blair's four hours in the not-so-hot seat on Friday were preoccupied with things like whether the ex-PM had had his eyebrows shaped to look more arched and evil.

From the outset, I had grave reservations about the war, and yet I have never doubted Tony Blair's good faith. It is perfectly possible for the man to be wrong and yet not be a liar. The real world is not binary. Nor do there seem to be right-or-wrong answers to many of the 105 detailed questions that Sir John Chilcot and his process-obsessed colleagues sent to Blair ahead of the hearing.

Blair had explanations, of sorts, for most of the key points. Was the Cabinet properly informed? Of course, though it was more concerned at the political fallout of going to war alongside a right-wing president than it was about the reliability of the intelligence on weapons of mass destruction. Not all cabinet members were in on all the planning, but then Margaret Thatcher hadn't even included her chancellor in her war cabinet. And most of the Government's position was anyway public. The then leader of the Commons Robin Cook was well enough informed to have resigned.

Asked when Blair first gave an unbreakable commitment to George Bush that Britain would back the US in military action, he implied that the undertaking came in phases: when he told the US president "you can count on us", he added "but here are the difficulties". He offered similar ambiguity on whether the question of regime change, illegal under international law, was a decisive motive for war.

And on the legality of the invasion he managed to confess that he had disregarded the attorney general's warning that attacking Iraq would be illegal, without further UN backing. But he insisted that he did so because he was confident that Lord Goldsmith would overturn that "provisional" judgement once he knew the full history of the negotiations. And the attorney general did change his mind after the detail of that process was spelled out to him when he went to Washington.

Those in the grip of Blair rage will find none of that convincing, and will continue to look for flaws and inconsistencies. Those better disposed to Blair will probably give him the benefit of the doubt. Where he did look on wobblier ground, for all his confidence and fluency, was in his dismissal of the lack of adequate forethought on how to handle the aftermath of the war. That plunged Iraq into years of chaos with 150,000 people dead, according to International Red Cross figures, and two million refugees still afraid to return to their homes.

"We thought that Iran would want to promote stability," he said blithely. Clearly he failed to foresee that Iran might want to intervene on behalf of Iraq's Shia majority, for decades under the thumb of Saddam's Sunni-dominated regime. "Our understanding of this is far better now than it was then," he said, dismissing as hindsight another point made by the panel. "That's far too stark a comment made with the benefit of hindsight," he said on a third occasion.

There was indignation from Sir John Chilcot about the fact that the inquiry has been given a sequence of frank private letters, handwritten by Blair to Bush in the run-up to the war, but then told that they cannot quote from them in their final report. They contain "important, and often unique, insights" into Blair's thinking and commitments, Chilcot has pronounced. Yet the ruling that they must not be published – made by Britain's most senior civil servant, Sir Gus O'Donnell, for fear that that might stifle frankness between the British prime minister and the American president in future – seems prudent, and will not inhibit Chilcot from drawing pointed conclusions from the documents.

For four hours, I dutifully watched all this, feeling that no more had been proved than Tony Blair's misplaced optimism, casual carelessness and occasional naivety in the presence of great power. But then he got to Iran. Iran, you will recall, he and George Bush thought would want to promote stability when they were planning the invasion of Iraq in 2003.

How things change. Iran today, Blair told Chilcot, is negative, destabilising, supportive of terrorist groups and doing everything it can to impede the Middle East peace process. It has spurned the hand of friendship President Obama extended to the Muslim world in Cairo in 2009. It is undermining the political process in Iraq because "it's an existential threat to Iranian theocracy for there to be progress towards democracy" in the country next door. And it is threatening the peace of the Middle East with its urge to develop nuclear weapons. It was, he said, a "looming challenge".

The mood had shifted. The passion had returned to his voice and the evangelical messianic glint to his eye. It was back to the future, and not just with Iran but with al-Qa'ida. There was a temptation to see that as "an alien encrustment, a perversion of Islam", he said, but it grows from a global ideology with much deeper roots. It is part of "a narrative which sees the West as fundamentally hostile to Islam, a narrative that has far greater reach than many of us would like to accept".

That was when we saw that Tony Blair has learnt nothing. He is still gripped by a Manichean dualism which sees the world divided between good and evil. Reality is rather messier. For all George Bush's rhetoric about the axis of evil, Shia Tehran has given very limited support to the Sunni extremists in al-Qa'ida. Iran has no long-term interest in promoting anarchy in Iraq; rather it wants a stable and prosperous market next door for its goods and services, and it wants an end to al-Qa'ida attacks on Shia communities in Iraq. Neither British nor Iranian interests are served by Blair's misrepresentation of Tehran as some unalloyed threat. He did not regret the decision to go to war, Tony Blair concluded, though of course he did have deep and profound regret for the loss of life.

"Too late," chorused the dead soldiers' mothers who sat in the public gallery. "A year too late."

And then came the whisper: "You don't mean it. Your lies killed our son." For some, on both sides, this war will never be over.