POLITICS isn’t big on decorum. Behind the superficial politeness of the honourable this and the right honourable that, the sharks are always scanning the water.

A ministerial sacking means promotion for someone else. A death begets a byelection. Crises, however grim, can be opportunities.

So it was quite a surprise to see the SNP come over all prim and prissy this week about discussing independence in relation to the coronavirus.

The prompt was Scottish Tory leader Jackson Carlaw joining the dots between the two as he looked ahead to the 2021 Holyrood election.

“I think it will look ridiculous if the first debate that the Nationalist movement want to have when we get to the other side of this is ‘Let’s go gung ho for independence next year’, then more fool them if they do,” he told the PA news agency.

“I think the public will look at that and say ‘Are you kidding?’”

He then twisted the dirk by observing Scotland was being helped through the outbreak by the UK’s “economic resilience and strength”.

The SNP’s reaction to this was to try to shut down the debate entirely, a sure sign Mr Carlaw had drawn blood.

“The last thing any Scottish politician on any side of the constitutional debate should be doing is trying to use the appalling crisis we all currently face as an argument for or against independence,” the party gasped.

Obviously, there’s a calculation to be made about how far to venture into regular politics during the pandemic.

The public has lost much of its appetite for the previous argy-bargy.

But for the party of independence to echo Theresa May and say now is not the time to argue for its cause at all?

Well, that was a moment.

Because if ever there was a time for the SNP to talk about independence - at least to itself - it is surely right now.

Its previous case for leaving the UK, of a healthier economy creating a fairer society, is being dismantled by Covid-19. Not speaking up would be a dereliction of the party’s mission.

The First Minister, as the tireless face of Scotland’s response to the emergency, is an understandable exception. But for the Yes movement’s sake, she cannot be the rule.

SNP MP Angus Brendan MacNeil had the right idea. He simply ignored the injunction from party HQ and tweeted that it was good Mr Carlaw brought up independence, as it let the SNP government mention it too and “highlight that dealing with your own problems unfettered... is better”.

Regardless of whether you agree with his point, it made perfect sense for Mr MacNeil to make it, to keep saying what he believes in, and not cede the floor to his opponents.

He could see Mr Carlaw wasn’t squeamish about a Unionist argument based on Covid-19. That reference to the UK’s economic resilience and strength was a straw in the wind.

Come the 2021 election, the Tories, Labour and LibDems will be arguing that the Union, far from being an abstract anachronism, proved its worth in this crisis. That when it really mattered, Westminster broke the emergency glass at the Treasury and hosed the country with money. That the insurance policy paid out.

READ MORE: Mark Smith: A message for nationalists: do not make the virus about Scotland versus England – it demeans you 

People will of course argue over the many failings, about testing, PPE and the threadbare state of the NHS and the welfare state going into this.

But the key message from the Unionist side, like it or loathe it, will be that the four-nations of the UK pulled together and got things done.

And while there were regional tweaks, Scotland was a core part and beneficiary of that collective effort. Go ask its Nationalist First Minister.

That argument is what the Yes movement, with its garlands of rosy hypotheticals, now has to overcome.

It must rethink its own arguments - not its beliefs, but its messages to the unpersuaded - and it needs to get a shift on. Above all, it needs to say how a fledgling state can take off in the worst recession in a century.

For what goes into the next white paper on independence now?

It was supposed to be rooted in Andrew Wilson’s Growth Commission, the SNP’s economic blueprint for a new Scotland.

It’s not Mr Wilson’s fault he didn’t factor in a pandemic. But it has made much of his work redundant.

Its research on how small countries can prosper is salvageable. But his calculations for the first decade of independence - based on long-term growth of 1.5%, halving a deficit of 7%, keeping debt below 40% of GDP - look like bygones of a different era.

As the report said, persuading No voters about the economics of independence will need “clear-sighted reality and a rigorous plan”.

But as we’ve learned, no plan survives contact with coronavirus, and economic plans least of all.

That particular pillar of the SNP’s case has now crumbled. The longer the crisis goes on, the more pages in the old prospectus will turn blank.

The one thing that could yet change the dynamic is Brexit. If the UK government refuses to extend trade talks with the EU in light of coronavirus and brings about a hard lurch to WTO terms in the depths of a recession, it will squander any credit it is accumulating at present, and remind a lot of Scottish voters why they wanted to wave Westminster goodbye.

READ MORE: Scottish independence support maintains lead in latest poll 

However the current refusal to change course probably owes more to the absence of the only Tory who can sell an extension to Leave voters than dogmatism. Only once the Prime Minister returns from convalescence can a pragmatic position prevail.

Even if the PM sticks to his original mad timetable, Ms Sturgeon cannot rely on it tipping the case for independence. She needs a new pitch as well.

Her announcement yesterday of an economic recovery advisory group acknowledged that. Despite insisting she has no time for party politics right now, she said the new group would plan how to build a “fairer, greener and more equal society” after Covid-19, a clear nod to independence.

It will be instructive to see how many politicians she sprinkles among the economists and business leaders to help steer it in that direction.

God knows, she needs something to go right for her cause just now.

Our columns are a platform for writers to express their opinions. They do not necessarily represent the views of The Herald.

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