Charm is politics’ deadliest weapon. It is not charisma, the authority to lead through an electrifying presence. It is a subtler, more intangible quality, possessed by Boris Johnson. He may be blatantly unqualified as Britain’s next prime minister, but following yesterday’s first-round leadership ballot, he is still odds-on favourite. The basis for this lies in his disposition of charm.

Johnson is the darling of the polls. He mesmerises punch-drunk Tories and disillusioned Labour voters alike. He emerges from his biographical record as incompetent, lazy, dissolute and a liar, yet the public’s response is that he is “our kind of liar”. He was sacked by the Times for story fabrication and was a wildly biased reporter while in Brussels. His default mode has always been that of standup comedian: funny, unpredictable, mildly dangerous. As the current campaign of his rival, Michael Gove, is derailed for far lesser sins, his campaign appears to glide forwards on sheer force of personality. The unfairness is grotesque.

Quick Guide Tory party leadership contest Show What happens next in the Tory party leadership race? As she announced on 24 May, Theresa May stepped down formally as Conservative leader on Friday 7 June, although she remains in place as prime minister until her successor is chosen. In a Conservative leadership contest MPs hold a series of votes, in order to narrow down the initially crowded field to two leadership hopefuls, who go to a postal ballot of members.

How does the voting work? MPs choose one candidate, in a secret ballot held in a committee room in the House of Commons. The votes are tallied and the results announced on the same day. In the first round any candidate who won the support of less than 17 MPs was eliminated. In the second round anybody reaching less than 33 votes was eliminated. In subsequent rounds the bottom placed contender drops out until there are only two left. The party membership then chooses between them. When will the results be announced?

The postal ballot of members has begun, and the Tory party says it will announce the new prime minister on 23 July.. Photograph: Neil Hall/EPA

Johnson is currently locked away by his handlers. This is not charisma – it is a man who cannot be allowed to cope even with a Commons election on his own. On Wednesday, he was allowed to launch his leadership bid with extreme selectivity. Apart from giving £10bn in tax cuts to the rich, he cited his qualities for high office by ignoring his dire period as foreign secretary and concentrating on his time as mayor of London. He claimed credit for handling knife crime, the 2011 riots, the financial crash and the Olympics. He was Pericles presiding over Athens.

This is farcical. The London mayor is largely a figurehead, who administers almost nothing. Johnson’s crime policy was simply to get rid of his police chief. He capitulated to the tube unions and was a sycophant to property speculation. He told me to my face that he would emphatically end his predecessor Ken Livingstone’s “Dubai-on-Thames” skyscraper obsession, yet he promptly doubled their number. He travelled to Malaysia to plead for cash to build towers of empty luxury flats, thus creating the London skyline that is his memorial. I visited one such tower in Canning Town, east London, this week, with 84 empty flats owned in absentia by a single far east investor. That was Johnson’s idea of “housing”. What the mayor did in excess was splurge money on vanity projects. His Thames cable car, his Stratford helter-skelter (“London’s Eiffel Tower”), his rear-entry buses with rear-entry locked, his water cannon that may not fire, his unnecessary super-sewer and wildly over-engineered Crossrail, all wasted staggering sums. A baffling £53m vanished on Johnson’s fantasy garden bridge, while Hammersmith bridge rotted up-river. The “Boris bike” scheme – in truth Livingstone’s – was supposed to cost nothing, but cost taxpayers nearly £200m in eight years. Johnson’s belated visit to the scene of some of the 2011 riots was an opportunity to be photographed with a broom.

Boris Johnson and Arnold Schwarzenegger on ‘Boris bikes’: ‘It was supposed to cost nothing but cost taxpayers nearly £200m.’ Photograph: Matt Dunham/AP

Johnson should shut up about his exorbitant mayoralty. He was not Pericles but Nero, a maestro of bread and circuses. His character was certainly engaging, shambolic, often entertaining, and he was a pleasure to be with. But his aides, desperate for any sign of “vision”, nicknamed him Boris the Boring. He admitted at one point that his mayoralty might be short-lived, given his anticipated move to Downing Street. Of that strategy it must be said, it worked. His London election success was extraordinary, not least for an Eton toff against Livingstone’s cheeky-chappie Cockney.

The Johnson personality is clearly not to be underrated. As democracy becomes less a matter of interests and resources, it falls back on secondary responses, on making people relaxed and comfortable about the world about them. Voters seem drawn to someone who does not take life too seriously, is casual about presentation and possesses eccentric unpredictability. People like laughing at politics, and Johnson appears a fellow human. He is preferable to the spouters of robotic cliches, such as Theresa May.

Charm is discounted by political science in favour of integrity, diligence, consistency – and charisma. That is because charm is like love, its values not analysable or susceptible to science. Yet it was deployed with aplomb by Ronald Reagan and Bill Clinton, and currently by the actor-president of Ukraine, Volodymyr Zelensky. Weaponised charm may yet be the new tool of tyranny.

‘A baffling £53m vanished on Johnson’s fantasy garden bridge, while Hammersmith bridge rotted up-river.’ Photograph: Johnny Armstead/REX/Shutterstock

These are the waters towards which British politics is swimming. Unless Jeremy Hunt and Michael Gove can promote some stop-Boris coalition, the backwoods of the Conservative party will vote for the only candidate likely to guarantee them a parliamentary majority. But to put that to the test, Johnson will have to secure a negotiated Brexit, rather than just precipitate a parliamentary crisis and a Tory implosion. That means he must revert to some version of May’s deal, and to some frictionless customs union for both Britain and Northern Ireland. Reality will soon be screaming at him, that there is no alternative. He is too intelligent not to know it.

Johnson’s shrewdest supporters are quietly selling the theory that their hero’s notorious “flexibility” is what makes him ideally suited to the task. Cynicism and hypocrisy are what the country needs. Johnson will waffle and dissemble and mis-state and un-promise, until the country finds itself miraculously on the other side of the Brexit abyss. Such is modern politics, that it must rely for clear guidance on a leader’s capacity to lie.

But a prime minister’s job is not that of mayor or even foreign secretary. It is of circus ringmaster rather than performer. Two of Johnson’s idols are reputedly Disraeli and Churchill, two masters of the art of volte-face, of a denial of the past, including their own. Both had recourse to pragmatism when events required it and both were accounted successes.

Come October, the odds are on Britain being desperate for no more posturing, no more economic machismo and no more fantasies about new trade deals. It will need one almighty climbdown, in favour of some version of May’s Brexit deal. If Johnson can deploy his charm to persuade the nation and its parliament to follow where common sense and circumstance force him to go, I will be the first to cheer. That is as far as my optimism can go.

• Simon Jenkins is a Guardian columnist