Bush's fury as ex-spokesman twists the knife

What happened? Not What Happened, the simple and declarative title of the political memoir that last week set Washington afire – but, what on earth happened? How did an outwardly meek, loyal and somewhat undistinguished White House spokes-man named Scott McClellan come to write a book that demolishes George Bush and his administration more woundingly than any published so far?

Most recent presidential spokesmen have burst into print after leaving office. Some are bent on settling scores, others indulge in unrestrained hero worship. But none has ever turned on his former boss as comprehensively as McClellan, saddened but, he says, at last wiser as he takes apart the Iraq war and "a presidency that veered terribly off course".

Democrats have been delighted, Republicans and the Bush administration have been enraged and appalled. But their fury, and the sensation the book has caused, arises not so much from what is in the book – its critique basically merely confirms what has become conventional wisdom about Bush and his war – but from the identity of the author.

For Scott McClellan is no outsider. Like Bush's closest advisers Karl Rove and Karen Hughes, he was part of a Texan praetorian guard that accompanied the 43rd President from the Governor's mansion in Austin to the most powerful job in the world.

He joined the team in early 1999, and at the White House was first deputy spokesman and then spokesman for the best part of three draining years until he was shunted aside in April 2006. That he was planning a memoir had long been known – but no one could have imagined the blockbuster that was in store.

The big publishers showed little interest. The advance from the small PublicAffairs imprint that took the plunge did not exceed five figures. By Wednesday, however, it had leapt to No1 on the Amazon list, and such was the public demand that that evening it was in the bookshops, even though it was not due to be published until tomorrow.

By Thursday, its author was doing the round of TV and radio talk shows. McClellan these days has lost a little weight and his sideburns are longer – but otherwise it was the same round-faced, robotic and relentlessly on-message figure of the middle Bush years. Except that his message had changed.

What Happened: Inside the Bush White House and Washington's Culture of Deception, to give it its full title, is no dazzling read, gushing with anecdotes. Nor is it an undisguised hatchet-job, cutting down former rivals and enemies. McClellan was a PC Plod at the spokesman's rostrum, and as a writer he is still a plodder. Only 40, he comes across as earnest, disillusioned, but above all sincere.

Yes, he is bitter, mostly at being left to dangle in the CIA leak affair. In 2003, he says, he was falsely assured by leading figures in the administration that they were not involved in the leak to the press of the name of the CIA officer Valerie Plame.

When it became clear two years later that McClellan's denials were "inoperative", his credibility was destroyed. When he was eased out of office in 2006, it came as a surprise to no one, not even McClellan.

Maybe resentment of his treatment led him to toughen the language of his book. But ultimately the CIA imbroglio is a sideshow. The crux of McClellan's book is his apostasy on Iraq, the issue that will come to define the Bush presidency. As he tells it, he first went along with the invasion, trusting – like most Americans – a President guided by a highly experienced national security team.

Now, he describes the war as "unnecessary" and a "strategic blunder". Bush had made up his mind to attack Saddam Hussein early on. He and his team (including McClellan) sold it by "propaganda", abandoning "candour and honesty" for the distortions of the permanent political campaign. Indeed one of Bush's hallmarks, according to his former spokesman, is an ability to deceive himself – in the case of Iraq, to convince himself that the case for war was far stronger than it was.

The tone is less angry than sad. McClellan recounts the realisation of the trusty retainer, as the scales drop from his eyes, that both the cause and the man he served were deeply flawed. The disclosure will undoubtedly make McClellan a rich man (not that, as scion of a noted Texas political family, he was ever on his uppers). It will also be ammunition to his critics, both Republican and Democratic. This is no bid for absolution, they say, but a cynical effort to boost sales.

For they are asking, why did he take so long to see the light? Why didn't he resign if he was so miserable? As it was, he displayed not the slightest qualms when defending a manifestly failed Iraq policy. McClellan's answer is that he experienced no epiphany, only a slow and painful disenchantment. Only gradually did he realise how the obsession with secrecy created "a large black hole in my understanding of what was really going on inside the administration".

The vicious attacks from Bush loyalists and others who worked with McClellan that he was out of the loop and thus doesn't know what he's talking about, only confirm the obsession. For if the very spokesman of the President is not told what the President is thinking and doing, then how on earth is the country to be told the truth?

What Happened paints a familiar picture of Bush. He is a talented politician, who possesses charm, wit and much shrewdness. But he is also utterly incurious – not stupid, as his most blinded critics would claim, but ignorant. "Is he dumb?" Barbara Bush, the former first lady, once mused about her son. "Dumb, yes, he's dumb as a fox."

As President, McClellan writes, Bush has been impatient of policy detail. He prefers to go with his gut, most dangerously on foreign affairs, about which he knew next to nothing when he took office. Since then, more perhaps than any president since Ronald Reagan, he has inhabited "the bubble" that entrapped McClellan as well, severing him from the real world. As McClellan put it in one interview last week, "only as you leave the White House bubble, can you take off your partisan hat and take a clear-eyed view of things".

Two individuals in particular will not be happy with this "clear-eyed view". One is Condoleezza Rice, who occupied the crucial post of national security adviser in the run-up to the war. Rice, says McClellan, was "more interested in accommodating the President's instincts and ideas than in questioning them or educating him".

As for Rove, the man hailed by Bush as "the architect" of his re-election in 2004, he did not create the excesses of government by permanent campaign (the Clinton administration had mastered that art) but he took it to a new level. "Rove's role was political manipulation, plain and simple," McClellan declares. In the end, this mentality "crippled" the Bush White House.

Washington now awaits the fall-out from the book. It's one more piece of bad news for Republicans in an election year full of it. Its impact on the 2008 campaign itself may be modest, given that John McCain, the presumptive Republican nominee, was already distancing himself from Bush. For the 70 per cent of Americans who disapprove of Bush, it merely confirms their views. The remaining minority of true believers will be convinced that McClellan is fit only for public lynching.

And between Bush and his former aide, the bonds are surely broken for ever. "One day he and I are going to be rocking on chairs in Texas talking about the good old days and his time as press secretary," Bush said as he publicly thanked McClellan in April 2006 for "a job well done". It's hard to imagine these two putting up their feet together on the porch any time soon.