‘MR Johnson, whatever you do, don’t pull out. I know you’ve done it before...”. Michael Gove’s odd remark about his rival for the Tory leadership, Boris Johnson, was interpreted by some observers as a dig at the ex London Mayor’s priapic adventures. “A disgraceful smear on Boris’s reputation,” as one Tory MP described it.

Mind you, if it was indeed a sexual innuendo it was surely the wrong way round, since Boris’s affairs have led to at least two extra-marital pregnancies. I suspect Michael Gove, who is as sharp as a tack, knew perfectly well how his ambiguous remark would be received.

It was designed to distract press attention from his cocaine confessions.

HeraldScotland:

Even if it wasn’t a sexual allusion, it was still astonishing to hear the politician who famously stabbed Boris Johnson in the back in the 2016 Tory leadership contest wielding the stiletto again.

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Mr Johnson has his chance to retaliate today as he finally launches his leadership campaign. But he’ll have a hard job getting a word in as he is relentlessly challenged on his moral fitness for office.

Expect every one of his lies, affairs, broken promises and his cocaine use to be exposed. How he allegedly connived in the assault of a journalist; was sacked by the Times for fabricating stories; made offensive remarks about Muslims. Remember that 2017 interview in which the former BBC presenter, Eddie Mair, called him “a nasty piece of work”.

Mind you, he’s not alone. I’ve lost count of the number of Tory leadership candidates who’ve admitted to using drugs. We’ve had Jeremy Hunt talking about reducing the abortion limit to 12 weeks; Esther McVey’s contretemps with TV’s Lorraine Kelly; and, of course, all those magic formulas for unlocking Brexit. It’s not so much a horse race as an unruly herd of unicorns trying to trip each other up.

Boris Johnson still leads by a horn, and is most favoured by the Tory membership. But today he’ll collide with reality as the media shred his proposal to hand up to £6,000 in tax cuts to people earning up to £80,000. His Tory colleagues have already set the scene.

Dominic Raab, the Thatcherite ex-Brexit Secretary, said the giveaway would paint the Tories as “the party of privilege”. Andrea Leadsom said the cuts would be “unworkable”. Rory Stewart called them “eye-watering”. In fact, about the only thing Tory candidates agree on is that Mr Johnson’s fiscal policies are rubbish.

However, there is a progressive side to Mr Johnson’s tax changes. He’s proposing to raise the threshold for the 40p tax band in England from £50,000 to £80,000. But he is also calling for the cap on National Insurance contributions to be lifted. At present, the NI burden is disproportionately laid on those earning the lower rate of tax, since it’s effectively frozen at 12 per cent for earnings above that. Successive Labour chancellors, since John Smith in the 1990s, have tried to lift the NI cap, and failed because of the public outcry.

However, this concession is more than outweighed by Mr Johnson’s income tax bung to the well-off. At a time when the country is barely recovering from austerity, handing thousands to the top 10 per cent of earners makes little moral or economic sense. Far better to give it to the legions of workers who’ve seen their pay frozen in the longest period of wage stagnation since the Napoleonic Wars. They at least will spend the money on goods in the high streets. The wealthy will bank it or buy property and shares.

Not only would Mr Johnson’s plans cement the Tories’s reputation as the party of class privilege, they could also destroy the Union itself. Nicola Sturgeon has frozen the higher rate tax threshold to £44,000 and has no intention of raising it. This means that employees earning above that would, in Boris Johnson’s regime, suffer a tax increase by paying more in National Insurance. The Scottish Parliament has no powers over NIcs.

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Perhaps Mr Johnson thinks he’s helping the Scottish Tory leader, Ruth Davidson, by giving her stronger evidence for the “SNP’s tax blitz on middle earners”. But it is more likely to blow her up. The NI hike will be portrayed by the FM as an outrageous imposition on Scots: Boris’s poll tax.

If it is ever implemented, that is. As this column has argued, nothing Mr Johnson says in this campaign should be regarded as a commitment. When he was London Mayor, he made a raft of promises on transport and congestion charging that never saw the light of day. Anyway, there’s no way his tax cut agenda would get through parliament.

The same goes for his promises on a No Deal Brexit. As rival Matt Hancock pointed out yesterday, hard Brexit will be stymied by MPs in the Commons. This is why I’ve argued that Mr Johnson is the candidate most likely to implement Theresa May’s Brexit deal. He’ll shift focus to the subsequent trade negotiations, which have nothing to do with the Withdrawal Treaty, and promise to deliver a Canada-style free trade agreement.

But he has to win first. Today’s grilling will show just how hard that is going to be. The front runner rarely wins in Tory leadership contests, because the rivals will do just about anything, short of actual defamation, to undermine his or her chances. The briefing war starts today.

This may explain why Mr Johnson launched his campaign, puzzlingly, with his unpopular tax give-away. As the Institute for Fiscal Studies noted, this would be most rewarding for wealthy pensioners, who don’t pay National Insurance. The 120,000-odd Tory membership has an average age well above retirement. It’s like a heat-seeking missile directed at the bank accounts of the Tory selectorate.

Whisper it, but Mr Johnson’s tax cut would also benefit employees whose salaries fall just below his new £80,000 threshold for higher rate tax. Like MPs and senior journalists on London papers. I’m sure that this will not for one-second figure in their minds as they decide which candidate is best suited to serve in Number 10.