Boris Johnson’s departure has poleaxed the independence movement. That, at least, is the received wisdom.

Obviously, the political demise of a man who sucked oxygen from every room will change the dynamics of Scottish politics. Heavens, the Scots Tories might get a UK leader they can actually support.

But whether that’s Rishi Sunak, Penny Mordant, Sajid Javid, Liz Truss or AN Other, it’s fairly safe to predict there’ll be no warm welcome in the glens.

And personality is just a minor factor. Liz Truss’ leaden attempts to channel the Blessed Margaret do make her almost unwatchable to left-leaning Scots of a certain age, whilst Rishi Sunak’s smarm, along with his non-dom wife, millionaire status and lack of working-class friends (according to a recently re-surfaced video) also put him on the back foot. Ben Wallace’s straight-forward manner might have commanded some respect, but he’s not standing. Just as well, because his stock would have plummeted immediately.

Why? No Tory leader has fared well in Scotland since Ted Heath’s Declaration of Perth supporting Scottish devolution, was roundly dumped by his successor. Boris is just the most disliked Tory Prime Minister in a long Home-Rule-denying list.

There was no ‘Cameron bounce’ in Scotland, no May magic - and as for that ‘nice man’ John Major, he said it had become ‘more respectable to be a Conservative ‘publicly’ in Scotland than for the last 13 years’ before losing every single Scottish Tory seat in the 1997 General Election.

What maddening to Scots personality trait did all these PMs share? Or did Scots simply look past personality to policies they didn’t support and hadn’t voted for, time after time?

If so, the fate of the next Tory PM will be the same as the last.

He or she will not carry the dead weight of Partygate, but will inherit the same bad policy choices – sparking an EU Trade War over axing the NI protocol and proceeding with a Bill of Rights that makes Rwanda deportations easier and gerrymanders future General Elections with its requirement for voter photo ID.

S/he will also be unlikely to index-link benefits, reinstate the Universal Credit cut or improve Britain’s position as the most unequal country in Europe bar Portugal.

And s/he will be a firm advocate of the real recruiting sergeant for independence according to Prof Sir John Curtice – Brexit.

“The decline in support for the Union pre-dates Boris becoming Prime Minister,” he said. “You can you trace it back to the spring of 2019. So yes, Boris is absolutely essential – but it is Boris’s legacy and [that] didn’t disappear [last week].”

Political analyst Anthony Salamone supports that view: “once a voter has decided to back ¬independence, they don’t usually turn back easily. I wouldn’t expect there to be an immediate change just on the basis of Boris Johnson leaving.”

Brexit is one issue that will keep many new recruits onside for independence – and another whopper is brewing. Every leadership contender bar Rishi Sunak is promising tax-cuts at a time of simultaneous crises that require strategy, spending and public investment. Some tax-cut pledges have already been costed at £40 billion per annum – the same as the existing defence budget.

Intelligent Scottish voters are bound to ask – how can a country with the worst predicted economic growth of any major country except Russia in 2023 afford to cut taxes? Is that policy wise or just necessary to cultivate a Tory membership so wired and unhinged that it actually wants to see Boris reinstated?

Can tax cuts produce enough growth to compensate for shrinking state coffers during a cost of living, climate and security crisis?

Past voting patterns suggest Scots would prefer increased state investment to accelerate a green transition, improve energy security and create jobs.

But none of the Tory leadership contenders will deliver that kind of future and thanks to Keir Starmer’s recent repudiation of the EU, the GDP-boost of re-joining the single market is also impossible within the UK. As Big Dog put it so succinctly – them’s the breaks. And Scots know it.

Dominic Cummings’ prediction of 'summer carnage' by Boris Johnson may be avoided if the Tories run their selection process at warp speed, deny the membership a say, and produce successor within weeks. But the woeful spectacle of a ‘hinging-on’ Boris and Westminster at its shabby, reality-denying worst will stay in Scottish minds for some time, not least because good luck or good timing placed an alternative template for independence in the public domain, just days earlier.

Without any prospect of a snap election – since the Tories are bound to lose - the route-map to another independence referendum is still daunting. That reality – and the likelihood of a second Project Fear – are the biggest difficulties facing independence, not the loss of Boris Johnson.

Certainly, both difficulties do arise from London not playing fair – something increasingly recognised by broadcasters like Channel 4’s Krishnan Guru Murthy who tweeted last week that Tory MPs could change the rules and have a second leadership vote within one month while Scots had to wait one generation for a second crack at independence.

But life’s not fair. The next referendum will be fought on a variety of issues, but it’ll also be a straight choice between EU and UK membership. That demands more action to explain the Scottish Government’s strategy to EU member states, more support for the Brussels lobbying plans of Europe for Scotland and more effort to create general support for Scotland’s right to choose.

The Constitutional Convention promised by Nicola Sturgeon in 2020 must be established – and that won’t be easy. But the first convention survived boycotts by the Tories (and ironically, the SNP) to produce a successful template for devolution. This time around, hard work is needed to persuade sympathetic individuals and Labour-supporting unions to participate – and that work should be starting now.

In short, never mind the tantalising distractions of a vicious Tory leadership battle. The SNP and Yes movement need to fix the roof while the sun shines. David Cameron got that right, at least.

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