There’s nothing like turbulence at Holyrood to get Scots in London in a froth. The two Andrews – Marr and Neil – are both wringing their hands at the events of the past week, the former with angst, the latter with glee.

Former BBC political editor Andrew Marr concludes the current political crisis shows the SNP had become far too smug and complacent for their own good (agreed), but the other Andrew, former Murdoch editor and founding chairman of GB News, insists that independence is “now dead for a generation, if not longer”.

Perhaps it was past his bedtime when he wrote that. How anyone could make such a rash prediction after the events of the last generation in Scottish politics, quite beggars belief.

A generation or longer? Let’s put that in context. It was 25 years ago this month that the Scottish Parliament convened for the first time and the devolution era began. The prevailing assumption then that devolution would “kill nationalism stone dead” (George Robertson) proved to be just a tad off. Alex Salmond and Nicola Sturgeon made it their life’s work to sow discontent with devolution while also skilfully posing as its protector. And it worked.

For five years after December 1999, no poll showed support for independence higher than 30 per cent (the period, incidentally, when one John Swinney was running the SNP). Robertson appeared to be right… only he wasn’t.

By 2014, 45 per cent of voters would back independence in a referendum. By 2020, support for it in the polls would exceed 50 per cent consistently for six months. And perhaps most pertinently of all, even when the SNP crashed and burned, as all hegemonic political parties must, the level of support for independence would remain steady at nearly half the electorate.

The Herald: Andrew Marr Andrew Marr (Image: free)

That of course is where we are now. So independence is not dead. Uncoupled from its spent SNP rocket boosters, support for it appears to have become sort of self-sustaining. Legions of voters still favour independence in spite of having learned the hard way that the SNP isn’t much good at making dreams come true.

In 10 or 15 years, who the heck knows? I certainly wouldn’t bet against the independence movement capturing disillusionment with a second-term Labour government to drive up support for independence to further highs.

No one knows if independence will happen in the next 30 years; from where we’re standing now, it doesn’t look altogether likely. But only the foolhardy would rule it out.

Let’s not mistake the stalling of progress towards independence with the campaign being over. And it has stalled, certainly. Humza Yousaf said on Monday it felt “frustratingly close”. Nonsense. With Labour likely to win the general election convincingly, there is no route for the next few years to an independence referendum.

But that doesn’t mean the goal is dead. The Yes campaign has a firm base on which to build – somewhere around 46 or 47 per cent of voters are already on side, at least in theory – and if the SNP end up in opposition that might well prove to be a good place from which to attract further support for leaving the UK.

It’s not a foregone conclusion that come 2026, the SNP will lose power at Holyrood –polls show them more or less neck and neck with Scottish Labour – but if they do, that could turn out to be a good thing for the independence movement.

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After the bloodletting that would inevitably follow defeat, the SNP would be able to regroup. Independence is a radical, insurgent, anti-establishment idea best sold from the outside. The SNP were masters for years at behaving like an opposition party while in office, but with failures of their own making piling up they can’t pull that trick off any more. They have become the tired establishment and need to leave.

You can see how then, outside government, they could focus on the main goal, of gathering sustained support for independence based on a more thought-through prospectus, capturing discontented Labour voters with their grass-is-greener message.

And they might have another advantage. Younger people have typically been more Yes supporting than older folk. It’s a fondly held nationalist view that they will continue to be so as they get older. That’s questionable, but we’ll find out. If it turns out to be true, then demographic change over the next 10 years will propel support for leaving the UK upwards.

And then… what? Support for independence needs to be in the upper 50s for a referendum to be credible. If it reached that level, it would both make it trickier for a future Westminster government to deny Scotland a referendum, and boost the chances of the Yes camp winning.

Can anyone really be confident that won’t happen?

Ten years is an age in politics; a generation is eons. It’s only a generation ago that the government of John Major was hurled out of Downing Street, an event that was followed by years in the political wilderness for the Tories. They were a laughing stock (remember William Hague with his baseball cap on backwards or Iain Duncan Smith as the spiritual successor to John Major’s grey Spitting Image puppet?). But even that didn’t last. By as soon as 2010 they were back in power and we’re still not shot of them.

The Herald: Pressure for independence is stable - and could easily growPressure for independence is stable - and could easily grow (Image: free)

There’s an important lesson in all this for those who want to preserve the UK union. The events of this month will soon enough be history but the campaign for independence won’t. Underlying Andrew Neil’s view is complacency, triumphalism – and wishful thinking. It may take a while, but the nationalist political movement will regain momentum; to dismiss the threat would be just plain foolish.

Labour, which has had the luxury of being a spectator to other parties’ travails, will soon have to show how it will meet that challenge. For Keir Starmer’s party, pretending it doesn’t exist could be fatal.