No one understands the brutality of Washington politics better than Donald Rumsfeld. He has practised a bit of it himself over almost four decades at the top. As a senior member of Richard Nixon’s Administration, then as the Chief of Staff and Defence Secretary for Gerald Ford, he gained a reputation as one of the most gifted of bureaucratic knife-fighters.

Back at the Pentagon under President Bush, and in alliance with his old friend Vice-President Dick Cheney, Mr Rumsfeld has proved adept at leveraging the harsh realities of politics to achieve ends that can leave colleagues bruised.

So he will have easily grasped the unforgiving logic that forced him out of the Pentagon after six turbulent years.

That did not prevent him sounding a note of bitterness in his brief appearance with President Bush. “I call to mind the words of Winston Churchill, who said, ‘I have benefited greatly from criticism and at no time have I suffered a lack thereof’.”

The scale of the electoral defeat for President Bush and his Republican Party required a drastic retooling if political momentum was to be restored in what is left of the Administration. The removal of a controversial and unpopular Defence Secretary inextricably associated with an unpopular war was the obvious first move.

The likely epitaph on Mr Rumsfeld’s career is that he was precisely the wrong kind of man for his times. His brusque, managerial style — he has been know to humiliate senior military officials in front of their peers — reflected a confident belief in the cleansing power of creative destruction. He had made his career destabilising conservative, slow-moving institutions and intended to do the same to the US military. But while that approach may have been appropriate in a time of peace it was ill-suited to a time of war, when instability leads to chaos and weakness.

For the 74-year-old Mr Rumsfeld the defeat presumably ended a political career marked at the last by failure.

After excelling as a student wrestler at Princeton and following a stint in the US Navy, Mr Rumsfeld entered Congress in 1962 as an ambitious Republican from Illinois. He was widely regarded as among the most likely of his generation to make it to the White House. Razor-sharp, with a penchant for exactitude of language that bordered on pedantry, he was known as a control freak, and ran President Ford’s White House with a micromanaging quality that would come to be his hallmark.

His first stint as Defence Secretary in the 1970s — as the youngest — was uneventful. His second — as the oldest — was anything but.

Mr Rumsfeld had spent the 1990s studying the military in the post-Cold War world and concluded that it was hopelessly ill-equipped to meet its new challenges. He came to the Pentagon in 2001 and set out on a path of “transformation”, shifting military resources from big, slow-moving units, to lighter, more mobile and technologically advanced capabilities.

His belief that the warfare of the future would differ radically from that of the past was spectacularly vindicated by the aftermath of the 9/11 attacks.

In the ensuing war in Afghanistan, agile US military forces toppled the Taleban and Mr Rumsfeld’s star was in the ascendant. But then came Iraq. The Defence Secretary, according to those who have worked with him, could barely disguise his disdain for the caution of many senior military officers and repeatedly overruled them.

When the initial victory turned to the warfare against insurgents, Mr Rumsfeld showed no sign of changing tack. It is clear from a number of books published this year that the Pentagon under Mr Rumsfeld was inadequately prepared for the guerrilla warfare and the blame for that rests squarely with the Secretary.

RUMMY'S WORLD

‘Reports that say that something hasn’t happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns — the ones we don’t know we don’t know’ February 2003

‘I would not say that the future is necessarily less predictable than the past. I think the past was not predictable when it started.’ 2003

‘We do know of certain knowledge that he [Osama bin Laden] is either in Afghanistan or in some other country or dead’ 2001

‘Freedom’s untidy, and free people are free to make mistakes and do bad things . . . Stuff happens’ On looting in Iraq after the 2003 invasion

‘Death has a tendency to encourage a depressing view of war’ 2003

‘You get a lot more with a kind word and a gun than you do with a kind word alone’ Quoting Al Capone to express views on international diplomacy in 1998

‘As you know, you go to war with the army you have, not the army you might want or wish to have at a later time’ 2004

‘We do have a saying: if you’re in a hole, stop digging . . . erm, I’m not sure I should have said that’ 2002

‘Be able to resign. It will improve your value to the President and do wonders for your performance’ 1974

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