Tom Sawyer​ cheats to win a Bible that he doesn’t want. He pretends to have memorised two thousand verses of the New Testament so that he can appear ‘great and conspicuous’. He’s undone when he’s asked to name the first two disciples. When Donald Trump said that the Bible was his favourite book, and then was asked by a reporter to name his favourite verse, he couldn’t lose because he refused to play: ‘I wouldn’t want to get into it because to me that’s very personal. You know, when I talk about the Bible it’s very personal. So I don’t want to get into verses, I don’t want to get into – the Bible means a lot to me, but I don’t want to get into specifics.’ At the moment, Trump claims more support among Evangelical Christians than any other potential candidate for president. Evangelicals like what he has said about abortion (‘I’m very, very pro-life’) and Obamacare (he’s promised to replace it with ‘something terrific’). And they like his assurance that when he’s elected president, God willing, he’ll compel shop assistants to go back to saying ‘Merry Christmas’ instead of ‘Happy Holidays’. But ask Trump’s supporters what they like most about him, and they say it’s the man himself. Like the gossips of St Petersburg, Missouri who think that Tom Sawyer ‘would be president, yet, if he escaped hanging’, they admire his chutzpah.

In 1885, Mark Twain published The Adventures of Huckleberry Finn and Friedrich Drumpf, apprentice barber, arrived in New York Harbor. He came from the village of Kallstadt, in southwest Germany, but his son and grandson would do a lot of business with Jews — why not avoid unpleasantness? And so in interviews and in his memoir, The Art of the Deal (1987), Donald Trump says that his paternal grandfather was Swedish. Friedrich did well selling horsemeat in the Klondike during the gold rush, running saloons and, very probably, brothels. But he was an alcoholic and died young. His oldest son, Frederick, Donald’s father, went to work as a builder while he was still a teenager. He built his first house in Queens for a little less than $5000, then sold it for $7500. He used the profits to build another house, then another. The buildings were solid enough, but his real genius lay in sussing out tax breaks and abatements, in availing himself of federal programmes that would pay him to keep building houses during the Depression, then apartment blocks for naval bases during the war, then entire neighbourhoods – Trump Village, Shore Haven, Beach Haven – for veterans returning to Brooklyn. According to Michael D’Antonio’s delightful new biography, one of Trump père’s schemes was to create an ‘independent company to buy used equipment’ – everything needed on a building site, excavators, tile machines – which he would then lease to his own projects for ‘as much as twenty times their actual cost’: he’d buy a truck for $2600, then rent it to himself for $21,000.

There would be investigations and hearings, and Fred Trump was criticised in the press for profiteering, but he was never prosecuted. When Donald says that politicians who accept campaign contributions are crooks – he’s the only one who’s ‘so rich I can’t be bought’ – he boasts he’s speaking from experience: his father’s rise was assured because of the megabucks he gave, all his life, to Democrats. The only person to give more money than Fred to the congressman Hugh Carey’s winning campaign to be governor of New York was Carey’s own brother. When the Trumps wanted the contract to develop Manhattan’s West Side railyards, the mayor of New York, Abraham Beame, told the city’s planning commission that ‘whatever my friends Fred and Donald want in this town, they get.’

In D’Antonio’s book, and in Gwenda Blair’s The Trumps: Three Generations that Built an Empire (2001), Fred Trump is clever, meticulous, hardworking, difficult to please, quick to anger and a bit of a prig. Rather than pay $2 a bottle for disinfectant, he sends samples of cleaning supplies to a chemist to find out what’s in them, then mixes his own for fifty cents a bottle. He rages when one of his apartments is given new windows even though the old ones were still serviceable, and he fumes when his married daughter refers to her own pregnancy: too indelicate a subject to be spoken of inside the home, since it implies that she has once had sex.

In September, Jason Horowitz, a reporter for the New York Times, interviewed Donald Trump to ask if his father, who had lived on Devonshire Road in Queens, New York, was the same Fred Trump of Devonshire Road in Queens, New York who was arrested in 1927 for taking part in a ‘battle’ in which dozens of New York City police officers were beaten by a mob of Ku Klux Klan members:

Q. Growing up, you lived on Wareham Place? A. We lived on Wareham, prior to my father building that one [on Midland Parkway] which was right next door but a street away. Q. Did your father live on Devonshire Road before that? A. That was a different one, that’s where my grandmother lived and my father, early on. Q. Have you seen this story about police arresting a Fred Trump who lived at that Devonshire address in 1927 after a Ku Klux Klan rally turned violent? A. Totally false. We lived on Wareham. The Devonshire – I know there is a road Devonshire but I don’t think my father ever lived on Devonshire. Q. The Census shows that he lived there with your mother. But regardless, you never heard about that story? A. It never happened. And by the way, I saw that it was one little website that said it. It never happened. And they said there were no charges, no nothing. It’s unfair to mention it, to be honest, because there were no charges. They said there were charges against other people, but there were absolutely no charges, totally false. Somebody showed me that website – it was a little website and somebody did that. By the way, did you notice that there were no charges? Well, if there are no charges that means it shouldn’t be mentioned.

In The Art of the Deal, Trump says that whenever a reporter is out to get him, he tries ‘to frame a positive answer, even if that means shifting the ground’. He admits that some people might call this ‘lying’, but he prefers the phrase ‘truthful hyperbole’.

There’s nothing in D’Antonio’s book about the Klan, but he gives a good account of the 1973 Department of Justice lawsuit against the Trump Management Corporation for refusing to rent apartments to African Americans. Donald insisted that his family wasn’t racist: they were just trying to avoid tenants who wouldn’t be ‘neat and clean’ or on welfare; his lawyer said that by interfering with how Donald ran his business the government was behaving like ‘storm troopers’, the ‘Gestapo’. The Trumps settled – they agreed they’d try to do better – but black people would continue to report that they had been turned away from empty apartments or quoted inflated rents. In 1989, when five black and Latino teenagers were arrested for raping a white woman in Central Park, Donald paid for full-page advertisements in New York newspapers, demanding the boys’ execution. When they were exonerated, he wouldn’t apologise: ‘Tell me, what were they doing in the park, playing checkers?’

Donald seems to have admired everything about his father except for his parsimony, his lack of fame, his insistence on never moving from his small office in a dull part of Brooklyn. ‘I wanted to try something grander, more glamorous and more exciting.’ He’s credited his ‘sense of showmanship’ to his mother, an immigrant from the Hebrides who had a lifelong obsession with the royal family, and a ‘great fighting spirit, like Braveheart’ (as portrayed by Mel Gibson). She raised her children in the church of Norman Vincent Peale, the positive thinking guru, who preached that guilt was unhealthy and ambition godly. One of Peale’s edicts: ‘Learn to pray big prayers: God will rate you according to the size of your prayers.’ Another: ‘never mention the possibility of failure, never think of it’ – just repeat, over and over and out loud: ‘God gives me the power to attain what I really want.’ Peale presided over Trump family funerals and weddings, and was Donald’s character reference when he applied for gambling licences. Trump told an Iowa summit that he could listen to Peale’s sermons ‘all day long’. They touched his heart.

It was always clear that he would go into the family business. He says that as a young man he was ‘the best baseball player in New York’ (there is zero evidence for this) and that he might have become a professional sportsman except that ‘there was no real money in it.’ A classmate remembers that he would boast that his father’s wealth was doubling every year: ‘He used to talk about his father’s business, how he would use him as a role model but go one step further.’ He punched a music teacher ‘because I didn’t think he knew anything about music’ and was sent to a military boarding school, which ‘taught me a lot about discipline’, and so he’s always identified with men who’ve seen action: ‘I felt like I was in the military in a true sense’ – after all, he’d had ‘more training militarily than a lot of the guys that go into the military’. He’s the right age to have been drafted into Vietnam, but in his memoirs claims that he avoided it because he had a ‘very high draft number’. He’s since admitted that actually a doctor signed off on a medical deferment for heel spurs, though they’d never disqualified him from playing baseball. Was the doctor a family friend? Trump won’t answer questions about this, although his campaign has released a statement reminding us that ‘Mr Trump was responsible for the building of the beautiful Vietnam War Memorial in lower Manhattan, for which he contributed a tremendous sum of money.’

Trump says that his great insight was realising that his life could be an advertisement for his work. ‘It’s really quite simple. If I were to take a full-page ad in the New York Times to publicise a project, it might cost $40,000’ – this was 1987 – ‘but if the New York Times writes even a moderately positive one-column story about one of my deals, it doesn’t cost me anything.’ In 1985, he announced that he was going to build the ‘world’s tallest building’ on New York’s West Side – it was never going to happen, but he got ‘attention, and that alone creates value’. Even his two divorces were ‘good for business’, he says, because tabloid coverage of his affairs made him seem virile. His executives fretted, but Trump told them it was great for the brand: ‘Guys love it.’ He bought a yacht though he hates being on the water and would never spend a night on it, because he didn’t want people to think he couldn’t afford one. The Trumps began developing luxury hotels, condos, casinos. Donald bought a football team, an airline. The Trump name was everywhere: so many deals! D’Antonio explains that lenders would kick in ‘extra money for operating or upgrading a new property’, and Trump needed the cash just to keep up with basic expenses. One of his executives admitted that ‘we never had any money on hand. That’s why we had to keep doing more deals.’ Trump’s company went bankrupt; he borrowed money on the strength of his future inheritance; his company went bankrupt again. He lost the yacht. When the stock market crashed on Black Monday, 19 October 1987, Trump told the press that of course he’d seen it coming and had made $200 million. According to Gwenda Blair, he’d actually lost $22 million. It was a necessary lie, since he’d just published The Art of the Deal, which promised that anyone could become rich if they just tried to be more like him. The ghostwritten book made the bestseller lists, even if it wasn’t – as he often says – ‘the number one selling business book of all time’.

‘I have made myself very rich,’ Trump says (over and over again). ‘I would make this country very rich.’ That’s why he should be president. He insists that he’s the ‘most successful man ever to run’, never mind the drafters of the constitution or the supreme commander of the allied forces. Bloomberg puts Trump’s current net worth at $2.9 billion, Forbes at $4.1 billion. The National Journal has worked out that if Trump had just put his father’s money in a mutual fund that tracked the S&P 500 and spent his career finger-painting, he’d have $8 billion. Wisely, D’Antonio refrains from offering an estimate of Trump’s net worth. When Timothy O’Brien, a New York Times journalist, suggested in Trump Nation (2005) that Trump probably wasn’t a billionaire at all, he was sued for libel. The case was eventually thrown out, as Trump must have known it would be, but O’Brien’s publisher is thought to have spent much more money defending the book than it could have made.

It’s not just vanity that requires Trump to claim that all his deals make gazillions: his current business requires it. Even when his projects fail – his golf course in Aberdeenshire, to take one example, has lost £3.5 million over the last two years – he makes money through letting other people put his name on their projects: no risk, little work, just a licensing fee upfront or a share of the profits. He doesn’t actually own the Trump Taj Mahal or Trump Palace or Trump Place or Trump Plaza or Trump Park Avenue or Trump Soho, or the many Trump buildings throughout South America, Turkey, South Korea and the Caucasus. Developers buy the use of his name because enough customers believe in it: ‘It’s not even a question of ego. It’s just that my name makes everything more successful,’ he says. And so there have been Trump board games and phone contracts, credit cards, mattresses, deodorants, chocolate bars that look like gold bars, cologne sold only by Macy’s (‘Success by Trump’). He made $200 million over 14 seasons by being the star of The Apprentice, playing ‘Donald Trump’, the richest, tycooniest man in the world. Between 2005 and 2010, Trump made more than $40 million from thousands of students who enrolled in entrepreneurship classes at ‘Trump University’. Some say it was a scam, and many of them have joined class action lawsuits to get their money back (one says that ‘for my $35,000+ all I got was books that I could have gotten from the library’). The attorney general of New York has filed a lawsuit against Trump for fraud.

‘Our country needs to be glamorised,’ Trump says, and he’s the one to do it. He takes credit for the art of misnumbering floors – why tell someone that they’re on the 72nd floor when you can really wow them (as in the Trump World Tower) by claiming it’s the 90th? To shift condos, he created a rumour that Charles and Diana, recently married, were on the verge of buying an apartment in Trump Tower, also that the queen insisted on using his helicopter when she was in the States because there wasn’t a better one in the country. ‘I only have one regret in the women department,’ Trump boasts, ‘that I never had the opportunity to court Lady Diana Spencer.’ According to Selina Scott, Diana said that the huge bouquets Trump sent to Kensington Palace gave her the creeps, but Trump says that if she hadn’t been killed he’d have ‘had a shot’. If instead of his current wife, a former Slovenian bikini model, Trump had married the former Princess of Wales, would his need to appear ‘grander, more glamorous and more exciting’ than his father have been satisfied?