Rumsfeld and his legacy: The departure of Donald Rumsfeld from his post as defence secretary marks the end of an extraordinary career at the centre of US policymaking for the 74-year-old who is now seen as the embodiment of the US-Iraq misadventure and the archetypal Washington hawk.
Rumsfeld, who first served in his present job in the Ford administration back in the 1970s, has combined a career in public service, where he acquired a reputation as one of the fiercest bureaucratic infighters, with a successful business career that President Bush persuaded him to interrupt to return to office.
Henry Kissinger once admitted that Rumsfeld was the only man to best him in Washington and his old friend vice-president Dick Cheney described Rumsfeld as his mentor.
After college Rumsfeld became a naval aviator and then launched into a political career, first as a congressional aide, and then, at the age of 30, winning election to the House from Illinois's 15th District. In 1969 he left Congress to join the Nixon administration as a domestic adviser, then accepting a posting to Brussels as Nato ambassador.
After Nixon's forced resignation Gerald Ford made Rumsfeld his chief of staff, then secretary of defence, presiding successfully over a department badly demoralised by Vietnam.
The election of Jimmy Carter saw him turn to business where he is credited with saving two major companies, GD Searle and General Instrument Corp. He made a lot of money and when he returned to the Bush cabinet in 2001 to add gravitas and experience, he was one of its several multimillionaires. He came back into public office with a coterie of neoconservatives determined to re-establish US global authority and to make good the mistake of not finishing off Saddam in the first Gulf war.
"We need to accept responsibility for America's unique role in preserving and extending an international order friendly to our security, our prosperity and our principles," declared a statement of foreign policy principles that Rumsfeld and others drafted two years earlier for the Project for a New American Century.
"History teaches us that weakness is provocative," he says.
Rumsfeld was also determined to transform what he saw as a hidebound, cold war-fixated US military into a modern fighting force, earning himself the immediate enmity of many in the senior military.
On September 11th, however, Rumsfeld was in his office in the Pentagon when it came under attack and went out to tend the wounded. He held the first administration press conference. He was experienced, authoritative, calm, reassuring.
His age became a virtue. He came into his own, his warnings of US vulnerability justified. And with budget constraints blown away by Osama bin Laden, the military would get, he believed, both resources and reform.
He would be the architect of the "war on terror", the campaigns in Afghanistan and Iraq, and the man who opened Guantánamo and defended its and the army's robust methods.
His planning for the Iraq war led to serious criticism within the military and his own department, where many officers complained that he deliberately underestimated the troop requirements to make the case for intervention more palatable.
But as he wrote in Rumsfeld's Rules, his compilation of truisms dating back to the 1970s: "If you are not criticised, you may not be doing much." And: "It is easier to get into something than to get out of it."