If Britain votes to leave the European Union on Thursday, the chances of Boris Johnson and Michael Gove running the country will increase. In such a nightmare scenario, we need to know what the two leading Brexiteers stand for and what they are likely to do to us if, as is not impossible, a discredited David Cameron is toppled. To find out how they would change Britain, I have been reading their books – everything from Johnson’s The Perils of the Pushy Parents: A Cautionary Tale to Gove’s Celsius 7/7 (with its clunky subtitle that some editor should have rejected: How the West’s Policy of Appeasement Has Provoked Yet More Fundamentalist Terror – and What Has to Be Done Now).

There is an immediate problem in trying to work out what they stand for: Boris Johnson. Even Johnson doesn’t know what he stands for. On the campaign trail in the 2005 general election he said: “What’s my view on drugs? I’ve forgotten my view on drugs.”

Johnson is to British politics what the Red Queen was to Through The Looking-Glass: a virtuoso of inconsistency. For instance, if you read The Perils of the Pushy Parents, his debut book of poetry from 2007 (and I strongly urge that you don’t), you’ll find the following argument (if that isn’t too strong a word):

“Loving parents, learn from me.

If your children crave TV

Tell them, OK, what the hell

You can watch it for a spell …

IF YOU READ A BOOK AS WELL.

(A proper book, you’ll understand

Like the volume in your hand.)”

There is lots more of this prosodically challenged guff. But that’s not the point. The point is that a few months before this poem was published, Johnson argued the opposite. He posted a rant against video games on his website: “Summon up all your strength, all your courage. Steel yourself for the screams and yank out that plug. And if they still kick up a fuss, then get out the sledgehammer and strike a blow for literacy.” Like the Red Queen, Johnson is capable of believing as many as six impossible things before breakfast. He once said of the former leader of the Labour party: “He is a mixture of Harry Houdini and a greased piglet. He is barely human in his elusiveness. Nailing Blair is like trying to pin jelly to a wall.” Blair might have replied: “Pot, kettle.”

Gove, by contrast, is utterly consistent, immovable granite to Johnsonian jelly. The ideas that Gove developed in Celsius 7/7, written shortly after the 7 July 2005 bombings in London, have guided many of his policies as a government minister.

For instance, in 2014, as David Cameron’s education secretary, Gove appointed Peter Clarke, former national head of counter-terrorism, to investigate the alleged Islamisation of Birmingham schools and rumours about children being tutored in extremism. Eyebrows were raised: why not an education professional, official or judge to run the inquiry? Reading Celsius 7/7 helps us understand why.

In that book, Gove effectively posed as a latter-day Churchill, indicting Britain for its policy of appeasement. “Nowhere has moral clarity been more lacking in British state policy over the last 10 to 15 years,” Gove wrote, “than in our approach to the Islamist threat.” Islamists were infiltrating education in the same way the Trotskyist entryists of Militant had taken over parts of the Labour party in the 1980s, he suggested.

Celsius 7/7 starts with a chilling image, that of Mohammad Sidique Khan sitting thoughtfully at a Yorkshire school where he was employed as teaching mentor. “His professional life was dedicated to helping the children of recent immigrants make the most of their opportunities in the United Kingdom,” wrote Gove. On 7 July 2005, Khan detonated a bomb on a Circle line train leaving Edgware Road tube station in London, joining three others in a suicide attack in which 52 died and 700 were injured. “They were not,” wrote Gove, “desperately poor and voiceless outsiders, Frantz Fanon’s ‘wretched of the earth’ driven to violence because no other option lay open to them to secure justice. They had enjoyed the freedoms and opportunities of the west, holding down respected jobs and living lives of relative comfort … As Khan himself proclaimed, in a videotape broadcast after his death, ‘We are at war and I am a soldier.’”

Like Khan, Gove thought he was at war. Like George W Bush, he saw the world in Manichean terms. Like political scientist Samuel P Huntington, author of The Clash of Civilisations, Gove was possessed by the idea that the primary post-cold war geopolitical struggle would be between western democracy and radical Islam. And when Gove came to political office, first as education secretary and then justice secretary, he put his anti-appeasement ideas into practice.

He had, for instance, a notorious argument with home secretary Theresa May. She wanted a narrow focus on individuals posing a security threat, he told former colleagues at the Times, while Gove wanted to take on ideas “to drain the swamp” before “the crocodiles reach the boat”.

Gove’s Celsius 7/7 was written in reaction to the London bombings of 7 July 2005. Photograph: Max Nash/AP

In Celsius 7/7, he developed another image. Chapter 8 was entitled The Trojan Horse and its suggestion was that the enemies of British values were already subverting democracy from within. Strikingly, in 2014, a leaked letter was published, alleged to be from Birmingham Islamists, ostensibly detailing a plot to take over schools in the area and make them adopt a more reactionary Islamic curriculum. It became known as the “Trojan horse letter”. Some supposed it a forgery; others, such as Gove, saw it as confirmation that British values were under threat.

One of Gove’s responses to the Trojan horse scandal in Birmingham was his announcement, in 2014, that in the future all of England’s 20,000 primary and secondary schools would have “to respect the fundamental British values of democracy, the rule of law, individual liberty and mutual respect and tolerance of those with different faiths and beliefs”. He added that teachers would be banned from the profession if they allowed extremists into classrooms. Celsius 7/7 was the diagnosis; his policies, ostensibly, the cure.

In 2006, Gove’s book was denounced by critics such as Steven Poole in the Guardian (“What universe is Gove living in? Why, the universe of ‘moral clarity’, a phrase that resounds throughout the book and which, as usual, announces a jejune cowboys-and-Indians worldview. Remarkably trite”) and even by the Daily Telegraph reviewer, who feared that Gove’s parallel between the cold war and the west’s war against the “totalitarian ideology” of global Islamism “is misleading, and even dangerous”. Intriguingly, though, Geoffrey Wheatcroft claimed in the Guardian in 2007 that Gove’s “Muslim-bashing diatribe Celsius 7/7 is given to every lucky person who joins the CFI [the Conservative Friends of Israel]”.

In 2014, the application of that book’s ideas to British politics was also attacked. Former Conservative minister Crispin Blunt accused Gove of using Britain’s national security council to promote “neocon” ideas that could encourage moderates to move towards Islamist extremism. Blunt argued Gove’s approach would be “impractical and counter-productive”. Why? “You would find that people who are in the shades of grey are then driven into being black because they are invited to choose between black and white.” That’s to say, if there is a Trojan horse in Britain subverting our values and helping terrorism thrive, perhaps its name is Michael Gove.

After reading Gove’s Manichean philippic, Johnson’s writings are a jaunty relief, particularly when he goes off-message. In his 2006 book The Dream of Rome, for instance, Johnson argued that Turkey should become a member of the European Union. What on earth was he on about? His chums in the leave campaign – Gove and defence minister Penny Mordaunt – think letting Turkey in would be bonkers. “This will not only increase the strain on Britain’s public services, but it will also create a number of threats to UK security,” said Mordaunt recently. “Crime is far higher in Turkey than the UK. Gun ownership is also more widespread.” Indeed, one argument Mordaunt set out for Brexit was that her boss, David Cameron, could not veto Turkey’s membership (a claim, to be fair, that the PM retorted was nonsense).

So what made Boris call for Turks to be admitted to the EU? He saw the Turkish people, not so much as a gun-toting, fast-breeding crime wave poised to break over the white cliffs of Dover, but as venerable and much-loved denizens of the cradle of civilisation. He called for Turkey to be admitted, “not just on grounds of religious tolerance, but also because Turkey, after all, was where the [Roman] empire survived for another 1,000 years until 1453. It would be good to bring the Turks in, and reunite the two halves of the Roman empire.”

Perhaps there was another reason for Johnson’s (if this isn’t too strong a word) policy proposal – his ancestry. As he wrote in a 2006 volume of collected journalism, Have I Got Views for You: “My father’s father’s father was a romantic Turkish politician … whose career ended in a series of judgments that were romantic and certainly conservative but unwise and sometimes reckless.”

Johnson’s view hasn’t always been in tune with leave’s anti-Turkish scaremongering. Photograph: Murad Sezer/Reuters

Romantic, conservative, unwise, reckless – add to that description “inconsistent” and you have Boris’s political philosophy. What does Boris stand for? Nuclear power. Why? “It is not just that nuclear energy is environmentally friendly in itself … It also offers the hope that we can restore British activity and prestige in the physical sciences, not just as an end in itself, but because if we have to rely endlessly on the Russians for our gas, and on the Arabs for our oil, then no nukes will be bad nukes,” (Have I Got Views for You, p85).

And then there was his call for the re-Britannification of Britain. By which he meant that we had a lot to learn from the US. “In the wake of [Enoch] Powell’s racist foray, no one had the guts to talk about Britishness, or whether it was a good thing to insist – as the Americans do so successfully – on the basic loyalty of immigrants to the country of immigration.” Like Gove, Johnson had Muslims in his cross-hairs: “If that means the end of spouting hate in mosques, and treating women as second-class citizens, then so be it. We need to acculturate the second–generation Muslim communities to our way of life, and end the obvious alienation they feel,” (Have I Got Views for You, p139). He didn’t explain how.

He also expressed strong, if contrary, views on racism. “When I shamble around the park in my running gear late at night, and I come across that bunch of black kids, shrieking in the spooky corner by the disused gents, I would love to pretend that I don’t turn a hair,” (Have I Got Views for You, p126). Do such sentiments make him a racist? By no means, Johnson argued. “In fact, I like to think my instincts, in this respect, are as blameless as those of the average Guardian reader; and the thing is I am guilty nonetheless, not of racism but of spasms of incorrectitude, soon over, soon regretted.” What fellow Tory Enoch Powell got wrong when he predicted foaming rivers of blood as Britain collapsed into racist rioting, Johnson argued, was to underestimate British tolerance.

The corollary? “[P]rovided we have a reasonable legal framework for minimising the problem – like the infrastructure to remove sewage – we could probably achieve the same results, if not better, if we axed large chunks of the anti-racism industry, stopped taxing people with the threat of legal action, and left a bit more of the struggle against racism to tolerance and common sense.” Again, how that would work was left obscure.

Nonetheless, rolling back the frontiers of the state thus is classic Boris. “The trick of the next few years,” Johnson wrote in 2005, “will be to show that you can have compassionate politics that are for the benefit of business and enterprise, and that you can gradually bear down on taxation and spending in a way that is good for everyone.” That trick, as you may have noticed a decade on, has not really been pulled off by David Cameron. Perhaps Johnson could succeed where our current prime minister and his chancellor have failed? Stop looking at me sceptically.

What did the Romans ever do for us? Boris Johnson thinks he knows. Photograph: Sportsphoto Ltd/Allstar

The model for the minimal state Johnson admires comes from his study of the Roman empire. “We would surely want the laissez-faire government of the high empire, in which the economy grew and people prospered with nominal bureaucracy and regulation,” he wrote in The Dream of Rome. Yes, there was slavery, but otherwise, if only the European Union had been more like the Roman empire, Johnson would no doubt have been sharing a remain platform with Cameron rather than trying to inflict on the prime minister his biggest humiliation since revelations about that thing he allegedly did to a pig’s head.

Near the end of The Dream of Rome, the Eton-educated Latinist argued: “It would be good to recapture that enormous public-spirited creative energy of the Romans, to say nothing of the efficiency that allowed them to rule an empire of 80 million with 150 officials.”

But we latter-day Europeans cannot hope to emulate imperial Rome. Why not? To understand why the European Union can never repeat its glories, I read chapter 20 of The Churchill Factor, Johnson’s bestselling 2014 romp through the life of his political hero. There, on page 297, Johnson goes back to 1950 and the British parliamentary debate about the Schuman plan – the offer of the French foreign minister that Britain join talks on creating a supranational body to oversee common European markets in coal and steel. “The clay is wet. The mould has yet to set,” wrote Johnson breathlessly. “Now is the moment when Britain could have intervened decisively; accepted the invitation from France – and jointly seized the steering wheel.” But, Johnson argued, it didn’t. Years, later, once the clay was dry and the mould had firmly set, Britain belatedly joined the EEC (forerunner of the EU). By then the steering wheel was under Franco-German control; the British could only complain from the back, like sulky children, about the direction the continent was heading.

If only, Johnson suggests, Churchill had been prime minister in 1950, Britain would have become a leading member of the European Coal and Steel Community and thus been in the driving seat. That, Johnson argued, was what Churchill, as leader of the opposition sought, but shortsighted socialists pooh-poohed. Had they not, then, Britain might have helped create a European Union fit for purpose – one that Boris Johnson, at least, would not have campaigned for us to leave.

If Johnson’s writings are worth reading, it is not for his policy proposals, any of which he could renege upon before breakfast, but for such intriguing “what ifs” – the counterfactual history of Britain.

For all that Johnson eulogises Churchill, he does not see his clay as from the same mould as his hero’s. While The Churchill Factor is blurbed as “essential reading for those who want to know what makes a great leader”, Johnson admits that “as a politician I am not worthy to loose the latchet of his shoes”. A latchet, apparently, is a narrow thong for fastening a sandal. Did Churchill ever wear sandals? Frankly I don’t know. What I do know, from reading these books, is that it is not great men who are leading us to Brexit, not latter-day Churchills, but the most chilling British double act since Little and Large.