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WASHINGTON - During the course of the Iraq war, Donald Rumsfeld, the Defence Secretary, has undergone the transformation from unlikely pin-up to a poster-boy for everything wrong about the US-led war and occupation.
Nothing has more marked his tenure than a confidence bordering on arrogance and an unwillingness to listen to advice.
In the early days of the war with confidence in Washington still high, Mr Rumsfeld, 74, had a profile that bordered on that of a celebrity.
His briefings at the Pentagon were popular viewing on cable television, his "Rumsfeld's Rules" were published and seized on as some fantastic wisdom while his obfuscating answers to questions were likened to poetry.
Once he famously said: "There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don't know. But there are also unknown unknowns. There are things we don't know we don't know."
>>Rumsfeld quotes - 'Known knowns'
But gradually, as the chaos and violence in Iraq grew, as it emerged that the claims that Saddam Hussein possessed weapons of mass destruction had been false and as it became apparent that there was a major disagreement between Mr Rumsfeld and many in the military over the conduct of a war that has cost the lives of more than 2800 US troops and perhaps 655,000 Iraqis, so his star waned.
With the war in Iraq the overriding factor in the Republicans' defeat this week, Mr Bush must have felt no longer able to resist calls for his resignation.
To what extent Mr Rumsfeld's resignation will change anything in Iraq is unclear, given the view of some experts that events on the ground are largely out of US control.
"I think that changing the Secretary of Defence is a way of creating the impression of change given the impossibility of the reality of change," said John Pike, director of the military studies group GlobalSecurity.org.
"I don't know what [James] Baker is going to come up with but it's not going to be very different from what they are doing now." Mr Baker, Secretary of State in Mr Bush's father's administration, is heading a study group to investigate how best to proceed in Iraq.
His group is due to report back before the end of the year.
Asked yesterday whether there would be a new direction in the war, Mr Bush told reporters: "Well, there's certainly going to be new leadership at the Pentagon."
If Mr Bush accepts the Baker group's recommendations, the man he identified yesterday as his new choice for Defence Secretary, Bob Gates, will be tasked with implementing them.
Mr Gates, currently president of Texas A&M University and a close friend of the family, was also a member of the administration of Mr Bush's father, serving as director of the Central Intelligence from 1991 to 1993.
He had joined the CIA in 1966. During the 1970s he was also a member of the National Security Council.
Last week Mr Bush said he wanted Mr Rumsfeld - who first served as Defence Secretary in the government of Gerald Ford - to serve out his full term.
But that was not enough to stop the continued calls for his resignation.
On Monday, a series of respected military newspapers widely read by members of the armed services said it was time for Mr Rumsfeld to go.
It said: "Rumsfeld has lost credibility with the uniformed leadership, with the troops, with Congress and with the public at large. His strategy has failed, and his ability to lead is compromised. And although the blame for our failures in Iraq rests with the secretary, it will be the troops who bear its brunt."
And the victory by the Democrats in securing the House only increased the pressure on Mr Rumsfeld.
At her first post-victory briefing, Nancy Pelosi, the House Speaker-in-waiting, said Mr Bush needed to replace him.
She said voters had demanded a change in course on the war in Iraq.
She added: "The one good place he could start ... is to change the civilian leadership at the Pentagon."
- INDEPENDENT