Donald Rumsfeld, the former US defence secretary who remained bullish even as his forces suffered serial setbacks in the early years of the Iraq War, allows himself flashes of regret in his memoir, noting he should have quit after the 2004 Abu Ghraib prison abuse scandal and admitting to occasional bouts of glibness.
In the book, Known and Unknown, Mr Rumsfeld, who was replaced at the end of 2006, reveals that his then boss, the former president George W Bush, had his eye on punishing Saddam Hussein within two weeks of the 9/11 attacks, even while in public the focus of military preparations was Afghanistan and the removal of the Taliban regime.
Mr Bush told him at the time to "take a look at the shape of our military plans on Iraq", he writes in the book, which is due to be published on Tuesday.
"Two weeks after the worst terrorist attack in our nation's history, those of us in the Department of Defence were fully occupied," he says. "[The President] wanted the options to be 'creative.' "
Although self-reproach makes appearances in the 800-page tome, excerpts of which have been seen by The New York Times and The Washington Post, Mr Rumsfeld suggests there was plenty of blame to go around. Dysfunction in decision-making arose partly because of the competing agendas of different agencies, his own included.
However, he implies that ultimately it was up to Mr Bush to take firmer control. "There were far too many hands on the steering wheel, which, in my view, was a formula for running the truck into a ditch," writes Mr Rumsfeld.
Among those coming in for knocks in the book are Colin Powell and Condoleezza Rice, respectively Secretary of State and head of the National Security Council (NSC) in the White House at the war's onset.
"Key differences were never clearly or firmly resolved in the NSC," Mr Rumsfeld asserts. "Only the President could do so." Mr Bush, he also writes, "did not always receive, and may not have insisted on, a timely consideration of his options before he made a decision, nor did he always receive effective implementation of the decisions he made."
Perhaps not surprisingly, Mr Rumsfeld by no means suggests that the war itself was a mistake. In a formulation we have heard elsewhere, including from former senior politicians in Britain, he holds to the theory that had the coalition forces not toppled Saddam, the whole region would be "far more perilous than it is today".
As for his own style of presentation, for example in the briefing room of the Pentagon, he was guilty of quips, he admits now, that would have been better unsaid, including "stuff happens" in reference to mass looting in Baghdad and "old Europe", a jibe at countries that were critical of the war, such as France and Germany. He would also retract the assertion that "we know where they are" regarding Iraq's supposed stash of weapons of mass destruction.
Early reaction yesterday included a riposte from Senator John McCain, who is reportedly described in the book's pages as having a "hair-trigger temper" and "a propensity to shift his positions to appeal to the media". The two men famously clashed on policy, with Senator McCain leading calls for increased troop levels that were eventually answered after Mr Rumsfeld's departure with the surge that began in 2007 and led to a turnaround in the war.
"I respect Secretary Rumsfeld. He and I had a very, very strong difference of opinion about the strategy that he was employing in Iraq, which I predicted was doomed to failure," Mr McCain told ABC television. "And thank God he was relieved of his duties and we put the surge in, otherwise we would have had a disastrous defeat in Iraq."
Mr Rumsfeld, who until now has kept clear of the political arena, says he twice offered his resignation to the president after the Abu Ghraib affair, which revealed egregious abuse of Iraqi prisoners by American soldiers in the now-infamous facility. He was twice turned down.
"Abu Ghraib and its follow-on effects, including the continued drum-beat of 'torture' maintained by partisan critics of the war and the president, became a damaging distraction," he says.
"More than anything else I have failed to do, and even amid my pride in the many important things that we did accomplish, I regret that I did not leave at that point."
Returning to the policy-makers, he accuses Ms Rice of failing to tell Mr Bush how things really were, papering over differences of opinion. He also describes the rift between the State Department, led by Mr Powell, and the Pentagon on post-invasion strategy. The former favoured a slow transition towards giving power back to the Iraqis while, under Mr Rumsfeld, the Pentagon wanted to see an interim government set up much faster.
Paul Bremer, who ran occupied Iraq for the first year, apparently did not enjoy Mr Rumsfeld's unfettered admiration. The author faults Mr Bremer for taking steps to delay any transfer of authority back to the Iraqis, saying this "inadvertently stoked nationalist resentments and fanned the embers of what would become the Iraqi insurgency". There are also references to Mr Bremer by-passing Mr Rumsfeld in his dealings with Washington.
Some of the book is dedicated to Guantanamo Bay and the controversies that erupted over the handling by the US of detainees from Iraq and the so-called War on Terror.
He suggests that the White House should have done more to involve Congress in setting new guidelines. "Looking back, I see there are things the administration could have done differently and better with respect to wartime detention," he writes.
As regards the dispute with Mr McCain and others over troop levels in Iraq, Mr Rumsfeld asserts that if the commanders wanted more soldiers they never told him that they did. Even so, he writes, "there may have been times when more troops could have helped".
Mr Rumsfeld's book follows a similar tome by President Bush, in which the former commander-in-chief offered a robust defence of the Iraq war and few mea culpas.
What he said...
... on wartime detainees
2002 "I haven't found a single scrap of any kind of information that suggests that anyone has been treated anything other than humanely."
Now "Looking back, I see there are things the administration could have done differently and better with respect to wartime detention."
... on President Bush
2003 Rumsfeld praised Bush's "eloquent and unwavering leadership".
Now "[Bush] did not always receive, and may not have insisted on, a timely consideration of options before he made a decision, nor did he always receive effective implementation of decisions he made."
... on tackling looters in Baghdad
2003 "Think what's happened in our cities when we've had riots, and problems, and looting. Stuff happens!"
Now "In retrospect, there may have been times when more troops could have helped."