Psychologist Oliver James analyses the behaviour of the American president

Guardian

Not long afterwards, staring at his vomit-spattered face in the mirror, this dangerously self-destructive man fell to his knees and implored God to help him and became a teetotalling, fundamentalist Christian. David Frum, his speechwriter, described the change: "Sigmund Freud imported the Latin pronoun id to describe the impulsive, carnal, unruly elements of the human personality. [In his youth] Bush's id seems to have been every bit as powerful and destructive as Clinton's id. But sometime in Bush's middle years, his id was captured, shackled and manacled, and locked away."

One of the jailers was his father. His grandfather, uncles and many cousins attended both his secondary school, Andover, and his university, Yale, but the longest shadow was cast by his father's exceptional careers there.

On the wall of his school house at Andover, there was a large black-and-white photograph of his father in full sporting regalia. He had been one of the most successful student athletes in the school's 100-year history and was similarly remembered at Yale, where his grandfather was a trustee. His younger brother, Jeb, summed the problem up when he said, "A lot of people who have fathers like this feel a sense that they have failed." Such a titanic figure created mixed feelings. On the one hand, Bush worshipped and aspired to emulate him. Peter Neumann, an Andover roommate, recalls that, "He idolised his father, he was going to be just like his dad." At Yale, a friend remembered a "deep respect" for his father and when he later set up in the oil business, another friend said, "He was focused to prove himself to his dad."

On the other hand, deep down, Bush had a profound loathing for this perfect model of American citizenship whose very success made the son feel a failure. Rebelliousness was an unconscious attack on him and a desperate attempt to carve out something of his own. Far from paternal emulation, Bush described his goal at school as "to instil a sense of frivolity". Contemporaries at Yale say he was like the John Belushi character in the film Animal House, a drink-fuelled funseeker.

He was aggressively anti-intellectual and hostile to east-coast preppy types like his father, sometimes cruelly so. On one occasion he walked up to a matronly woman at a smart cocktail party and asked, "So, what's sex like after 50, anyway?"

A direct and loutish challenge to his father's posh sensibility came aged 25, after he had drunkenly crashed a car. "I hear you're looking for me," he sneered at his father, "do you want to go mano a mano, right here?"

As he grew older, the fury towards his father was increasingly directed against himself in depressive drinking. But it was not all his father's fault. There was also his insensitive and domineering mother.

Barbara Bush is described by her closest intimates as prone to "withering stares" and "sharply crystalline" retorts. She is also extremely tough. When he was seven, Bush's younger sister, Robin, died of leukaemia and several independent witnesses say he was very upset by this loss. Barbara claims its effect was exaggerated but nobody could accuse her of overreacting: the day after the funeral, she and her husband were on the golf course.

She was the main authority-figure in the home. Jeb describes it as having been, "A kind of matriarchy... when we were growing up, dad wasn't at home. Mom was the one to hand out the goodies and the discipline." A childhood friend recalls that,"She was the one who instilled fear", while Bush put it like this: "Every mother has her own style. Mine was a little like an army drill sergeant's... my mother's always been a very outspoken person who vents very well - she'll just let rip if she's got something on her mind." According to his uncle, the "letting rip" often included slaps and hits. Countless studies show that boys with such mothers are at much higher risk of becoming wild, alcoholic or antisocial.

On top of that, Barbara added substantially to the pressure from his father to be a high achiever by creating a highly competitive family culture. All the children's games, be they tiddlywinks or baseball, were intensely competitive - an actual "family league table" was kept of performance in various pursuits. At least this prepared him for life at Andover, where emotional literacy was definitely not part of the curriculum. Soon after arriving, he was asked to write an essay on a soul-stirring experience in his life to date and he chose the death of his sister. His mother had drilled it into him that it was wrong when writing to repeat words already used. Having employed "tears" once in the essay, he sought a substitute from a thesaurus she had given him and wrote "the lacerates ran down my cheeks". The essay received a fail grade, accompanied by derogatory comments such as "disgraceful".

This incident may be an insight into Bush's strange tendency to find the wrong words in making public pronouncements. "Is our children learning?" he once famously asked. On responding to critics of his intellect he claimed that they had "misunderestimated" him. Perhaps these verbal faux-pas are a barely unconscious way of winding up his bullying mother and waving two fingers at his cultured father's sensibility.

The outcome of this childhood was what psychologists call an authoritarian personality. Authoritarianism was identified shortly after the second world war as part of research to discover the causes of fascism. As the name suggests, authoritarians impose the strictest possible discipline on themselves and others - the sort of regime found in today's Whitte House, where prayers precede daily business, appointments are scheduled in five-minute blocks, women's skirts must be below the knee and Bush rises at 5.45am, invariably fitting in a 21-minute, three-mile jog before lunch.

Authoritarian personalities are organised around rabid hostility to "legitimate" targets, often ones nominated by their parents' prejudices. Intensely moralistic, they direct it towards despised social groups. As people, they avoid introspection or loving displays, preferring toughness and cynicism. They regard others with suspicion, attributing ulterior motives to the most innocent behaviour. They are liable to be superstitious. All these traits have been described in Bush many times, by friends or colleagues.

His moralism is all-encompassing and as passionate as can be. He plans to replace state welfare provision with faith-based charitable organisations that would impose Christian family values.

The commonest targets of authoritarians have been Jews, blacks and homosexuals. Bush is anti-abortion and his fundamentalist interpretation of the Bible would mean that gay practices are evil. But perhaps the group he reserves his strongest contempt for are those who have adopted the values of the 60s. He says he loathes "people who felt guilty about their lot in life because others were suffering".

He has always rejected any kind of introspection. Everyone who knows him well says how hard he is to get to know, that he lives behind what one friend calls a "facile, personable" facade. Frum comments that, "He is relentlessly disciplined and very slow to trust. Even when his mouth seems to be smiling at you, you can feel his eyes watching you."

His deepest beliefs amount to superstition. "Life takes its own turns," he says, "writes its own story and along the way we start to realise that we are not the author." God's will, not his own, explains his life.

Most fundamentalist Christians have authoritarian personalities. Two core beliefs separate fundamentalists from mere evangelists ("happy-clappy" Christians) or the mainstream Presbyterians among whom Bush first learned religion every Sunday with his parents: fundamentalists take the Bible absolutely literally as the word of God and believe that human history will come to an end in the near future, preceded by a terrible, apocaplytic battle on Earth between the forces of good and evil, which only the righteous shall survive. According to Frum when Bush talks of an "axis of evil" he is identifying his enemies as literally satanic, possessed by the devil. Whether he specifically sees the battle with Iraq and other "evil" nations as being part of the end-time, the apocalypse preceding the day of judgment, is not known. Nor is it known whether Tony Blair shares these particular religious ideas.

However, it is certain that however much Bush may sometimes seem like a buffoon, he is also powered by massive, suppressed anger towards anyone who challenges the extreme, fanatical beliefs shared by him and a significant slice of his citizens - in surveys, half of them also agree with the statement "the Bible is the actual word of God and is to be taken literally, word for word".

Bush's deep hatred, as well as love, for both his parents explains how he became a reckless rebel with a death wish. He hated his father for putting his whole life in the shade and for emotionally blackmailing him. He hated his mother for physically and mentally badgering him to fulfil her wishes. But the hatred also explains his radical transformation into an authoritarian fundamentalist. By totally identifying with an extreme version of their strict, religion-fuelled beliefs, he jailed his rebellious self. From now on, his unconscious hatred for them was channelled into a fanatical moral crusade to rid the world of evil.