One of the defining aspects of George W Bush’s presidency is his professed belief in God. Yet what really are his religious beliefs? The question, which seems central to understanding his presidency, never receives a satisfactory answer. Indeed, one religious figure close to him soon after his conversion was shocked to find that he talked about sex rather than theology and says that a lot of his faith seemed to be politically calculated.

Bush’s religion has often been described as evangelical. But unlike most other evangelicals, he blithely uses profanity and as governor of Texas he would play poker. He doesn’t pay tithes, he doesn’t try to convert others – one of the central obligations in most evangelical denominations. And he didn’t raise his daughters in the faith.

What Bush clearly does believe in is the personal, transforming and sustaining power of belief in God. Having a personal relationship with God, praying and reading the Bible daily were the tools he used to get control of his life more than 20 years ago.

They made it possible for him to control his drinking, keep his family together after his wife Laura threatened to leave him, manage his aggressive behaviour, cope with the burden of a heroic father and attain success.

With his behaviour under control, he began to gain the confidence of his father, Vice-President George H W Bush, who was having a problem winning the support of evangelical Christians for his bid for the presidency in 1988. Bush Sr regarded televangelists as snake-handlers and swindlers. But with the help of his eldest son and an evangelical minister called Doug Wead, he won the presidency.

The crucible of the campaign forged a close relationship between George W and Wead. “Weadie”, as George W called him, says the candidate’s son spent an inordinate amount of time talking about sex.

Bush Jr was so anxious to avoid any whiff or rumour of infidelity (there were rumours about his father) that he asked Wead to stay in his hotel room one night when he thought a young woman working on the campaign might knock on his door.

“I tried to read to him from the Bible, because by that time he was sending me these signals,” Wead told me. “But he wasn’t interested. He just rolled over and went to sleep.”

Wead said Bush resisted religious overtures as firmly as sexual ones. “He has absolutely zero interest in anything theological – nothing,” Wead said. “We spent hours talking about sex . . . who on the campaign was doing what to whom – but nothing about God. And I tried many, many times.”

Wead also recalls the son’s expressions of his own political interest. The campaign had prepared state-by-state analysis of the electorate. “When he got the one on Texas, his eyes just bugged out,” Wead remembered. He recalled that Bush said: “This is just great! I can become governor of Texas just with the evangelical vote.”

With the various roles he played as Bush Jr’s life counsellor, political adviser and spiritual companion, Wead became in the late 1980s the first in a series of what might be described as surrogate family members to George W.

What Karl Rove would do in helping Bush launch his political career in Texas, and Dick Cheney in helping him define his presidency, Wead did in helping Bush assert and establish his independent identity as a person of faith. But the experience left Wead troubled about the sincerity of Bush’s beliefs. “I’m almost certain that a lot of it was calculated,” he says.

He was particularly concerned about Bush’s rebellious daughters, Barbara and Jenna. Why hadn’t Bush called in the preacher Billy Graham who had helped to convert Dubya?

“If you really believed that there’s some accountability to life, wouldn’t you have Billy Graham come down and have a magic moment with your daughters? Are you just going to let them go to hell? You have all these religious leaders coming through. If it changed your life, wouldn’t you invite them to sit down in the living room and have a talk with your daughters? Or is it all political?”

Once elected, Bush Sr mishandled the religious right. In 1992 his share of the evangelical vote fell and he lost to Bill Clinton. George W became the keenest student of that defeat and he followed Wead’s advice when successfully bidding to become governor of Texas, where the political landscape had been reshaped by the rise of the evangelical movement.

As he and Rove later mapped out his presidential bid, Bush faced a new problem: how to retain the support of the right-wing evangelical leaders that he privately called “wackos” without being so closely identified with them that the association would alienate other voters. The answer was to expand his support for religiously based treatment for drug and alcohol abuse into “faith-based initiatives”, his signature social policy.

The phrase he picked up from Wead that encapsulated this philosophy was “compassionate conservatism”. The word “compassionate” had special overtones to born-again Christians, referring to their duty to be Good Samaritans. But to nonevangelicals, it simply sounded like a way of saying “not all that conservative”. It exemplified Bush’s ability to speak in code, using language with special meaning for evangelicals that sounded innocuous to everyone else.

An agnostic, Rove thought talking the talk was enough and that the candidate did not need to stroke the leaders of the religious right, to Wead’s dismay. Envy over Rove’s closer relationship with Bush may have pushed Wead towards an act of betrayal that he tried to portray as a service to history: secretly tape-recording nine hours of his private telephone conversations with Bush in 1999 and 2000. These tapes, of which I’ve obtained a partial copy (not from Wead), provide a glimpse of the man behind the public mask. They capture Bush thinking aloud and rehearsing answers to questions expected on the campaign trail.

On one, he acknowledges illegal drug use decades back. “Doug,” Bush says, “it doesn’t just matter [about] cocaine, it’d be the same with marijuana. I wouldn’t answer the mari-juana question. You know why? Because I don’t want some little kid doing what I tried . . . I don’t want any kid doing what I tried to do [pause] 30 years ago.”

But the more interesting revelation is how politically Bush thinks about religion. Speaking of an upcoming meeting with evangelical leaders, he notes: “As you said, there are some code words. There are some proper ways to say things and some improper ways. I am going to say that I’ve accepted Christ into my life. And that’s a true statement.”

The tapes reveal how political the faith of George W Bush is. Wead said that during the countless hours the two spent talking about religion over a dozen years, they discussed endlessly the implications of attending services at different congregations, how Bush could position himself in relation to various tricky questions and how he should handle various ministers and evangelical leaders. But the substance of Bush’s own faith never came up.

Wead told me that he now struggles with the question of how sincere Bush’s expressions of devotion ever were. He often goes over their conversations and the many memos he sent to Bush advising him how to woo the religious vote. “As these memos started flowing to him, he started feeding back to me what his faith was,” Wead said. “Now what is interesting for me, and I’m trying to understand is, was I giving him his story?”

Bush’s skill at “Jesus talk” raises an interesting problem. I’ve edited six books of Bushisms which collect hundreds of examples of the president’s verbal clumsiness. The patterns of these slips testify to some sort of relatively minor, undiagnosed language processing impairment akin to dys-lexia. But Bushisms are only one aspect of a complex verbal picture.

Growing up, Bush developed a glib facility with language that compensates for his disability. In private conversation he is quick-witted and funny, using focused tools of memory and physicality to create intimacy. In private he can be profane and get in your face, swearing “like a sailor” in a 1999 campaign interview with Tucker Carlson, a conservative reporter he expected to protect him, or telling staff that he would kick Saddam Hus-sein’s “sorry motherf****** ass all over the Mideast”. But in scripted and more formal settings, Bush is capable of dignified eloquence.

The greatest surprise is that Bush’s verbal clumsiness is sometimes matched by an impressive degree of precision. In a political context he is sensitive to the resonance and nuance of his terminology. He has always avoided the kind of evangelese that arouses the concern of secular citizens. He seldom uses such terms as born again, saved, Jesus, sinner, heaven or hell. Instead, during the 2000 campaign he chose more generic words: God, charge, heart, love, faith, spirit, service and prayer. To irreligious ears these sounded merely like elevated diction. Christian evangelicals, however, recognised them as references to the born-again religious experience.

In the event, Bush won only 68% of the evangelical vote in the presidential election in 2000, and nearly lost the contest. According to Rove’s calculations, 4m evangelical voters stayed home on election day. This poor performance meant Bush had a big job to do in cultivating the religious right in advance of the next election in 2004. It made passing a faith-based bill urgent. But implementing a faith-based policy proved far more difficult than promoting one. What worked in Texas ran aground in Washington because the national political spectrum was more liberal and secular.

John Dilulio, the first head of the Office of Faith-Based and Community Initiatives, left in disgust after six months and, in an interview for Esquire magazine, complained that there was no serious discussion of domestic policy or apparatus for developing it. His deputy, David Kuo, quotes Bush shouting: “Well, is he [Dilulio] right, or isn’t he? Have we done compassion or haven’t we? I wanna know.”

Years later he might still be wondering. There is essentially no faith-based programme beyond a minuscule $30m “compassion fund” that channels grants to politically sympathetic Christian groups. The chief work of the White House faith-based office turned into putting on conferences in swing states at which it touted breaking down largely nonexistent barriers and encouraged church groups to apply for grants that weren’t available. In his memoirs, Kuo quotes Rove at the outset of the administration demanding: “Just get me a f****** faith-based thing.”

Margaret Spellings, Bush’s first domestic policy adviser, expressed a similar frustration. “Just get me a damn faith bill. Any bill. I don’t care what kind of bill. Just get me a damn faith bill,” she said.

Kuo’s view is that Bush got snookered by Rove and other aides. The president never understood – or noticed – that the faith-based programmes he dictated never got implemented. He soon discovered, anyway, that what mattered to religious leaders was not government funding but influence on policy throughout the government where it intersected with abortion, evolution and other matters on the evangelical agenda. And this Bush and Rove gave them.

Kay Coles James, a prominent evangelical, was made head of the White House office of personnel. She put evangelicals in sensitive positions at justice, interior, state, health, the Food and Drug Administration, Nasa and the Centers for Disease Control. Even applicants to the Coalition Provisional Authority in Iraq were vetted for evangelical status – not because it mattered to their work, but on the straightforward principle of political patronage. The spoils system appeased Bush’s evangelical constituents.

The secular misunderstanding of Bush is that his relationship with God has turned him into a harsh man, driven by absolute moral certainty and attempting to foist his evangelical views onto others. Many of those who know Bush best see the religious influence in his life cutting in precisely the opposite direction. As one of the evangelical staff members in the White House told me over lunch last summer, Bush’s religion has made him more genuinely humble and less absolutist in the way he defends his views.

Believing that he, too, is a lowly sinner, he has learnt to be more tolerant of the faults of others. But if his eternal perspective improves his personality, it diminishes any ability to take in ambiguity or complexity. He told Senator Joe Biden early in his presidency: “I don’t do nuance.”

That line was probably spoken with self-deprecating irony, but it captures a truth about the intellectually constricting lens of his faith. Bush rejects nuance not because he’s incapable of engaging with it, but because he has chosen to reject it. Applying a crude religious lens that clarifies all decisions as moral choices rather than complicated trade-offs helps him fend off the deliberation and self-contradic-tion he identifies with his own father.

But closing one’s mind to complexity isn’t mere intellectual laziness; it’s a fundamental evasion of freedom, God-given or otherwise. A simple faith frees George W from the kind of agonising struggle that his father went through in handling the largest questions of his presidency and helps him to cope with the heavy burden of the job. But it comes at a tragic cost. A too crude religious understanding has limited Bush’s ability to comprehend the world. The habit of pious simplification has undermined the decider’s decision-making.

© Jacob Weisberg 2008

Extracted from The Bush Tragedy by Jacob Weisberg published by Bloomsbury on February 4 at £16.99. Copies can be ordered for £15.29 including postage from The Sunday Times BooksFirst on 0870 165 8585 Jacob Weisberg is editor of slate.com

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