Jack Straw said today he could have stopped Britain joining the invasion of Iraq if he had refused to back Tony Blair's decision to go to war in support of the United States.
In a lengthy submission to the official Iraq Inquiry, the former foreign secretary described his decision to back military action in March 2003 as "the most difficult I have ever faced in my life".
But Mr Straw, who is now the Justice Secretary, said he had never "backed away" from the choice that he made then and fully accepted the responsibilities that flowed from it.
He said the question of whether to back military action in support of the US had posed a "moral as well as political dilemma" which was "profoundly difficult".
He acknowledged that if he had refused to support it, Mr Blair would have been unable to carry the Government or Parliament.
"I was fully aware that my support for military action was critical," he said.
"If I had refused that, the UK's participation in the military action would not in practice have been possible.
"There almost certainly would have been no majority in either Cabinet or in the Commons."
Mr Straw acknowledged that the failure to find weapons of mass destruction - the justification for the invasion - had "undermined trust" but insisted that the decision to go to war was taken on the basis of the best available evidence.
"I made my choice. I have never backed away from it, and I do not intend to do so, and fully accept the responsibilities which flow from that," he said.
"I believed at the time, and still believe, that we made the best judgments we could have done in the circumstances. We did so assiduously, and on the best evidence we had available at the time."
He said that while intelligence played a "significant part" in the assessment of the threat posed by Saddam Hussein, it was not the only factor.
"My starting point on the assessment of the threat was what was publicly known about Iraq's WMD programmes, and its behaviour going back more than a dozen years," he said.
"It was that judgment - not intelligence - which lay at the heart of the UK Government's strategy for disarming Iraq, by diplomacy backed by the potential use of force."
He underlined the importance of "staying close" to the US in British decision-making at the time.
"There was also the enduring spectre of Suez over British foreign policy, which led to an all-pervasive view that the UK should so far as possible seek to 'stay close' to the United States," he said.
"I shared with the Prime Minister the view that the best approach for the UK was indeed to 'stay close' to the US administration and seek to persuade them that any action against Iraq had to be through the United Nations."
Mr Straw told the inquiry it was never British policy to achieve "regime change" in Iraq.
He pointed out that overthrowing Saddam had been part of official US policy since an Act of Congress signed by former president Bill Clinton in 1998.
But it was only after the September 11 2001 attacks that the Americans began to decide that they should do something about it, he said.
Mr Straw said: "We did not share the policy of regime change as a purpose of our foreign policy with the United States.
"It was not our policy in 2002, it was not our policy in 2003 and there would have been no legal base for it ever to be our policy."
Mr Straw said that prior to Mr Blair's meeting with George Bush at the President's Texas ranch in Crawford in April 2002 - 11 months before the invasion - there had been a debate within the Government on how the Americans should be "handled" over the Iraq issue.
He said he had made clear Britain could not have supported the US policy of seeking to overthrow Saddam.
"That was off the agenda as far as the UK was concerned. A foreign policy objective of regime change I regard as improper and also self-evidently unlawful," he said.
"It had no chance of being a runner in the UK, it certainly would not have got my support. The case therefore stood or fell on whether Iraq posed a threat to international peace and security by reason of its weapons of mass destruction."
Pressed by inquiry member Sir Roderic Lyne as to whether Mr Blair shared his view, Mr Straw said: "I think the best way to find that out is to ask him. We are two different people."
Sir Roderic retorted: "But one government. I am trying to find out what the government's policy is."
Mr Straw replied: "It is no great surprise to know that people at senior levels in government hold different views and debate those. What I had to offer the Prime Minister was my best judgment and my loyalty."
Mr Straw appeared to distance himself from what Mr Blair wrote in private letters to Mr Bush in the run-up to the 2003 invasion.
Mr Blair's former foreign policy adviser Sir David Manning told the inquiry in November of a note from the prime minister he took to Washington in July 2002 stressing that Britain could support any action against Iraq only if they had been through the UN.
The contents of the memo have not been made public.
Inquiry panel member Sir Roderic Lyne, a former diplomat, asked Mr Straw if he felt "entirely comfortable" with the way Mr Blair expressed himself to Mr Bush in this letter.
The former foreign secretary was at first reluctant to answer, saying: "I happen to place a high value on the confidentiality of relations with foreign states."
But eventually he admitted: "Would I have written the memo in the same way? Probably not, because I am a different person."
Mr Straw explained that Mr Blair was viewed with "considerable suspicion" by Mr Bush's Republicans because he had been very close to Mr Clinton.
He said: "He had to build up a relationship... I don't think you can criticise Tony Blair for trying to work out where this chap was coming from and trying to get alongside him."
Mr Straw said he believed he saw all the private memos Mr Blair wrote to Mr Bush.
"I saw some of them after they were written, I saw some of them in draft. It depended really on the circumstances," he said.
By contrast, former defence secretary Geoff Hoon told the inquiry this week that he did not see the personal letters to the US president.
He said: "The prime minister was a great note-writer and it would not surprise me at all that there were private notes that he would send to the president, moreover that he would have had private conversations with the president that I would not necessarily have been privy to."
Mr Straw suggested that previous British foreign policy failures had an impact on the thinking of officials and ministers over Iraq.
He told the inquiry: "Alongside, as it were, the lesson of Suez, which was stay close to the Americans, there was the lesson of the Falklands, which was take notice of the intelligence."
Mr Straw admitted it had been an "error" not to make clear in the Government's Iraq weapons dossier that the claim that Saddam had WMD which could be launched in 45 minutes did not refer to missiles.
"Plainly that reference should have been much more precise because it only ever referred in the intelligence to battlefield weapons," he said.
"That was an error and it is an error that has haunted us ever since."
He stressed however that the judgments that were made at the time that Saddam did have WMD were not based solely on the intelligence.
"They were informed by what I saw on the public record, they were informed by the intelligence, they were informed by my analysis of the behaviour of the Saddam Hussein regime over very many years," he said.
"The case for taking Iraq seriously was in no sense based on the intelligence alone. The intelligence supplemented what we knew already about the threat. It went with the grain. There was no reason not to believe the intelligence."
He said that he had genuinely believed that the strategy finally agreed with the Americans in September 2002 to seek to disarm Saddam through the UN could have succeeded in avoiding war.
"We were embarked on a strategy which, in my view, could easily have led to the peaceful resolution of this dispute. That was fundamentally the approach of the British Government," he said.
He added: "A satisfactory result would have been compliance (by Iraq) and no war. I don't regard the war ... I would never use the adjective 'satisfactory' for that."
The United Nations Security Council approved resolution 1441 on November 8, 2002, paving the way for the return of weapons inspectors to Iraq.
Mr Straw insisted that Britain would not have gone to war if the weapons inspectors had found that Saddam was complying with the terms of the resolution.
He said: "That would have been the end of it from our point of view.
"I don't know what the United States would have done. But there would have been no case whatever for us taking part in any military action and the strategy of 1441, which was to resolve this by peaceful means, would have succeeded."
Mr Straw added: "I certainly didn't want war."
The former foreign secretary suggested that the then-top UN weapons inspector, Dr Hans Blix, had since "glossed" his position in the run-up to the invasion of Iraq.
Mr Straw said: "There are some of those who were involved who sought to give an account of what they were saying at the time without gloss.
"There were others who have sought to give an account of what they thought they were saying at the time with gloss. And I think the jury is out on which camp Dr Blix is in."Reuse content