Like dictators and presidents of banana republics, Boris Johnson is eager to build monuments to his own greatness. Thus, when Thomas Heatherwick, designer of the Olympic cauldron at the 2012 London games, proposed spanning the Thames with a “garden bridge”, Johnson seized on the idea. He was just beginning his final term as London’s mayor, and a “Boris Bridge” would be a far grander and more enduring legacy than Boris Bikes.

What followed was, by any standards, an unmitigated catastrophe. Heatherwick and the engineering company Arup were awarded lucrative contracts to design and build the bridge following a public tendering process that was blatantly – almost criminally – rigged in their favour. When it was pointed out that Heatherwick had built just one bridge, whereas a prize-winning rival had built 25, Johnson blithely retorted: “Michelangelo had probably never built a duomo or had never painted the roof of a chapel before he did the Sistine Chapel.”

The construction contract was awarded to Bouygues after various pre-conditions were abandoned. It was awarded before any sort of viable business plan was produced, the requisite funding secured, or the necessary land and licences procured. The projected cost soared from £60m to more than £200m, and the notion that the bridge would be entirely funded by private donations was quietly jettisoned. By the time Sadiq Khan, Johnson’s successor as mayor, finally scrapped the project in 2017 it had cost taxpayers £46m without a brick being laid or bucket of concrete poured.

Typically, Johnson refused to be held to account or to accept responsibility for this fiasco. In a scathing report, Margaret Hodge, the former chair of the Commons public accounts committee, said: “I deeply regret that Boris Johnson, the London mayor ultimately responsible for all the decisions and actions taken on the Garden Bridge, refused to co-operate with this review, either in person or in writing and despite several requests.” She also noted that no records were kept of key meetings and discussions – a failure she described as “completely unacceptable when decisions around spending public money are being made”.

The Greater London Assembly’s oversight committee forced Johnson to appear before it under threat of subpoena, but he blustered, obfuscated, changed the subject, blamed others, professed not to remember key details and claimed – in the face of overwhelming evidence to the contrary – that “not a single penny of taxpayers’ money was wasted”. Len Duvall, who chaired the committee, said he used “all the tricks… rather than take responsibility for the project”, and added: “The rules are for others, not for him.”

Will Hurst, the managing editor of the Architects’ Journal, who has won awards for his magazine’s investigation of the scandal, told me: “It’s an utter disaster and Johnson has not taken responsibility for that. He’s tried to deflect blame on to others like Sadiq Khan who cancelled the project. He’s allowed Transport for London officials who did his bidding to take a lot of the flack.

“It’s an astonishing failure and loss of public money and Johnson has been extremely disingenuous about why it happened. The rules were bent and broken to try to force it through because it was his priority as a ‘grand projet’ to leave behind.” Yet Johnson sails blithely on, unashamed and unrepentant. The Garden Bridge would have merely spanned the Thames. The man who would be Britain’s next prime minister now dreams of building bridges across the English Channel to France, and across the Irish Sea to Northern Ireland.

***

On 6 July, Johnson endorsed Theresa May’s Chequers plan for leaving the European Union, though he did tell the specially convened cabinet session at the Prime Minister’s country retreat that selling it would be like “polishing a turd”.

David Davis then resigned as Brexit secretary and Johnson reconsidered. On 9 July, fearful of being outflanked, he announced his own resignation as foreign secretary – “second over the parapet” as one commentator observed. “I have practised the words over the weekend and find they stick in the throat,” Johnson explained in a letter published in defiance of the usual convention that a minister’s resignation letter is released at the same time as the prime minister’s response.

Johnson has an expensive lifestyle to maintain – all those ex-wives and mistresses, children and love-children. But he was not out of pocket for long. Within days he had resumed his old job as a Daily Telegraph columnist, contemptuously ignoring the rule that forbids former ministers from accepting new positions for three months after leaving the cabinet without the express approval of the government’s Advisory Committee on Business Appointments.

The Telegraph is paying Johnson £275,000 a year for his weekly column, and there is no doubt who is getting the better deal. Britain’s biggest broadsheet has become Johnson’s megaphone, his personal Pravda. Alongside large pictures of Johnson in statesmanlike poses, it regularly splashes his latest excoriating attacks on the Prime Minister across its front pages.

“Scandal of Brexit is not that we’ve failed, but that we have not tried”, the headlines proclaim. Or “It’s time to believe in our Great Britain”. Or “May’s Irish Brexit plan is a disaster, warns Boris”. Inside it publishes, entirely uncritically, his 4,000-word diatribes. “He should be paying us for these advertorials,” said one disgusted Telegraph journalist. A Telegraph executive told a friend he was “utterly, utterly appalled that all this money is being spent on this person, and that all his uncouth and ignorant takes on things are now taking over the newspaper every Monday”.



Illustration: André Carrilho

Johnson has a curious way of displaying his gratitude for such largesse and fawning coverage. He has posted his articles on his Facebook page almost as soon as they have appeared in the Telegraph, thus undermining the paper’s hopes of enlisting thousands of online subscribers to read them. (The Telegraph’s print circulation has halved over the past decade, to less than 400,000.) On the eve of October’s Tory conference, Johnson gave his first post-resignation interview – in which he called May’s Chequers plan “deranged” – not to the Telegraph, but to the rival Sunday Times. His hugely controversial comparison of the Chequers agreement to a suicide vest wrapped around the British constitution likewise appeared not in the Telegraph, but in an article for the Mail on Sunday. But then anyone who looks to Johnson for loyalty looks in vain.

And so the Johnson bandwagon trundles on – fuelled by fantastic promises to restore Albion’s lost glory, oiled by his ebullient personality, cheered on by a credulous public and compliant press, brushing gaffes and scandals aside, crushing conventions, insulting allies and breaking every rule of the road. Before we know it, that bandwagon could well be rumbling down Whitehall and in through the gates of Downing Street.

***

Boris Johnson would be the most ill-qualified occupant of No 10 in modern British history. By rights he should be utterly disqualified. He has none of the qualities required to fill a post once occupied by Winston Churchill, Margaret Thatcher and Clement Attlee – just a bumbling humour and colourful turn of phrase that he employs to dupe and manipulate.

Integrity? This is a man who was sacked by the Times for inventing a quote, made his name by filing largely fictitious stories for the Telegraph from Brussels, broke a solemn promise to Conrad Black that he would not seek a parliamentary seat while editing the Spectator, lied to the Tory leader Michael Howard about his affair with a Spectator columnist, cheated time and again on his wife, led a thoroughly mendacious Brexit campaign, and is congenitally treacherous and disloyal – as David Cameron and Theresa May can testify.

Principle? As mayor of London, Johnson was pro-business, but now he tells a private gathering: “Fuck business.” He used to favour immigration, but now leads a movement determined to raise the proverbial drawbridge, while likening Islamic women wearing burqas to bank robbers and letter boxes. Having once accused Donald Trump of displaying a “stupefying ignorance” and being “unfit” for office, he now – behind closed doors – expresses admiration for the US president. Indeed, he has become a sort of Trump-lite himself.

Leadership? Johnson has Churchillian delusions, but Churchill rallied the nation against the existential threat of Nazism in a moment of supreme national crisis. Johnson seeks to rally it against the illusory threat to British sovereignty posed by our European friends and allies in a time of peace and relative prosperity. He has succeeded only in dividing Britain more deeply and bitterly than anyone can remember.

Experience? Johnson was well-suited to the job of merrymaker-in-chief as mayor of London during the 2012 Olympics, but he has held just one ministerial job – that of foreign secretary. His two-year tenure was distinguished by no great achievements save perhaps for his role in encouraging international action against Russia following the Salisbury poisonings. He failed to develop any sort of Johnsonian foreign policy, and was largely silent on key issues such as Syria, North Korea and climate change (he told astonished diplomats that his priorities were saving elephants and quality education for girls).

He advanced no post-Brexit strategy or vision for the UK beyond the glib phrase “Global Britain”. At a time when he should have been helping to lubricate our withdrawal negotiations, and strengthening our ties with future trading partners, he flew round the world giving needless offence with his silly quips and gaffes.

A senior Foreign Office figure who observed him closely told me he struggled to remember a worse foreign secretary, and delivered this withering assessment: “He was entirely focused on his own advancement and promotion. He spent his whole time grandstanding and driving people to distraction. He had no grasp of details. He had appalling relations with No 10. There was not a single European minister who took him seriously. It was all bluff, bluff and seat-of-the-pants stuff. He was exasperating and there was a massive sigh of relief when he left the building… No one has created more havoc to less effect in terms of British interests.”

***

In October, Johnson addressed 1,500 adoring supporters at a fringe meeting at the Conservative party conference in Birmingham. They had queued for three hours to attend. They outnumbered the audiences that most cabinet ministers managed to muster in the main conference hall. They and the media had flocked to hear the speech of a man who was scarcely still bothering to conceal his ambition to replace May as prime minister, but his performance was far from prime ministerial.

Johnson knew the line that would win him the next day’s headlines: “This is the moment to chuck Chequers.” The rest was vaudeville, the lack of real substance disguised by his vivid language and the hunks of red meat he tossed to the faithful.

It began with a characteristic piece of faux-humility. Philip Hammond’s forecast that Johnson would never be prime minister was, he said, “the first Treasury forecast in a long time to have a distinct ring of truth”. There was the ritual Labour-bashing: “this Tony Benn tribute group… this weaselly cabal of superannuated Marxists, of Hugo Chávez-admiring, anti-Semitism-condoning, Kremlin apologists.” There were the staple applause lines – calls for tax cuts, right-to-buy, stop-and-searches, a better-funded NHS, a swipe at the bankers responsible for the 2008 financial crash.

But the section on Brexit verged on demagoguery. He raged against submitting “our institutions forever and indefinitely to foreign rule”. He warned that the Chequers plan would lead to the United Kingdom being “paraded in manacles down the Rue de la Loi [in Brussels] like Caratacus”. He suggested the officials responsible for it should be prosecuted under a 14th century statute that says no foreign court or government should have jurisdiction in this country.

This was Johnson at his hyperbolic, jingoistic, irresponsible worst. He invoked a menacing, fantasy Brussels that simply does not exist outside his own imagination. He acknowledged none of the enormous complexity, or dangers, of disentangling ourselves from a political and economic union of which we have been a leading member for 45 years.

He offered no solutions of his own, accepted no responsibility for the acrimony of Brexit, and finished with a phoney profession of support for the beleaguered Prime Minister. He urged his followers “to back Theresa May in the best way possible – by softly, quietly and sensibly supporting her original plan [for a hard Brexit]”.

***

As a nation, we have long prided ourselves on the sanity, stability and relative moderation of our political system. We have tended to snigger at countries such as Italy, with their Berlusconis and Beppe Grillos. But in Johnson we now have a charlatan of our own who is perilously close to winning power.

The Garden Bridge debacle offers a glimpse of how he has managed to come this far. As with his Brexit promise of a proud, independent Britain restored to its former glory, he painted a beguiling vision with himself as its champion. He pursued that vision with a cultish zeal and scant regard for costs, details or practicalities. Corners were cut. Legitimate concerns were brushed aside. Unwelcome facts were ignored. Critics were dismissed as naysayers when all that was really needed, or so he contended, was boldness and boundless belief. It was like mothers telling children that they will only see fairies if they really, really believe in them.

Even in his appearance before the London Assembly’s oversight committee in March, when the true scale of the fiasco had become apparent, Johnson described the cancellation of his self-aggrandising project as a “bitter disappointment”, expressed regret that he had not completed it while he was mayor, and blamed Sadiq Khan for failing to give it the “political push it needed”.

The aborted bridge cost the taxpayer £46m. The cost to the nation of a Johnson premiership would be vastly greater.