Jacob Weisberg, editor of Bush-bashing website Slate.com, has now psychoanalysed the US President.

President Bush’s verbal gaffes have become legendary. “Is our children learning?”, he once asked; “I know how hard it is to put food on your family”; “You teach a child to read, and he or her will be able to pass a literacy test”. But most of these malapropisms would probably have been forgotten were it not for 44-year-old political journalist Jacob Weisberg, who published them on slate.com, the internet magazine he edits.

Now, he says, he is doing “penance” for helping to “cultivate the idea that Bush is dim-witted”. His new book, The Bush Tragedy: The Unmaking of a President, is a psychological analysis of the outgoing leader.

It argues that the President’s flawed relationship with his father is at the root of his failure in office. George W, says Weisberg, has always vacillated between trying to emulate his father, and distancing himself from him.

Thus, he followed in the former President’s footsteps to Yale (as did Weisberg), into business in Texas and into politics — always less successfully. But once President, he deliberately rejected his father’s way of doing things. While Bush Sr was “thoughtful, moderate and pragmatic”, George W taught himself to take decisions instantly and never to change his mind. Where the father was detail-oriented, the son was interested only in the broad outline of policies, and left implementation — often disastrously — to others.

The worst way to promote a policy to the 43rd President was to tell him it was what the 41st would have done; the invasion of Iraq, according to Weisberg, was not to avenge George Bush Sr — but to outdo him. “None of this is in the open. Bush doesn’t have much awareness of it,” Weisberg says. “He thinks he respects his father — the hostility and anger is all submerged. They don’t fight, but he doesn’t reach out to his father for advice.”

Bush Sr, meanwhile, is “frustrated in his inability to help his son and at some level feels a sense of responsibility”. The first President Bush has several times burst out crying at public events involving his sons and, Weisberg claims, “it’s not because he’s happy”.

Back in the White House, George W has constructed for himself an alternative family, composed of Vice-President Dick Cheney, political guru Karl Rove, and Condoleezza Rice — who, as National Security Adviser, once referred to him as “my husb—” before correcting herself. Herein lay more tragedy. Cheney, Bush’s “foreign-policy father”, steered him towards a hawkish strategy overseas and used him to create a more powerful presidency, for which Bush has been roundly criticised.

Rove, meanwhile, tried to use Bush to create a Republican coalition that would dominate the political map for generations, in the process alienating the centre. The reason they were able to influence him so heavily, says Weisberg, is partly because they understood his dynamic with his father and used it to control him.

So how does Bush feel about his presidency as it comes to a close? “Whether at some level there’s the recognition of failure, I don’t know,” says Weisberg. “He feels that part of his job is projecting a sense of confidence, and to project that he has to feel it. He brainwashes himself to feel that.”

The Bush Tragedy, by Jacob Weisberg, is published by Bloomsbury at £16.99