Recently I had a conversation with a very high-ranking British civil servant who has worked right at the heart of the UK Government. It crystallised my thinking around the future of independence.

That senior civil servant is a thoughtful, highly-intelligent and genuinely non-partisan individual. They give credence to the case for independence where it’s due, and credence to the case for the Union where it’s due. They are the definition of "even-handed". The positions they’ve held in government mean I can’t identify them, but anonymity doesn’t erode the relevance of the message. We began by talking about what the “implosion” of the SNP means for independence.

Broadly, polls show support for independence remains steady, with voters basically divided down the middle. The two most recent polls put independence support at 46%, and support for the Union at 47% and 48% respectively.

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The previous poll had Yes on 51% and No on 43%. Prior to that the game flipped: No was on 50%, and Yes on 45%. So, really, Scotland is in constitutional stalemate.

Most of us appear to have made our minds up. In polling, "Don’t Knows run usually between 5-10%.

Crucially, these polling figures come amid the collapse in support for the SNP. In polling for the next General Election, the SNP and Labour are neck and neck on 35%. Long gone are the days when the SNP regularly polled in the mid-to-high forties.

To me, it’s been clear for a while now that support for independence has pretty much decoupled from support for the SNP. Many moderate Yes voters are simply sick of the SNP and prepared to give Labour a chance - not in hope and glee and belief in Keir Starmer or Anas Sarwar, but simply to get the Tories out.

That high-ranking civil servant believes much the same. “The further south you go and the closer to Westminster you get,” they said, “the more people conflate a rather spectacular political implosion with a collapse of ideas and trends, and that’s not true, that’s not happening. The level of support for independence is still pretty extraordinary.”

I couldn’t agree more, I said. It’s absurd to think that simply because a large swathe of independence supporters have sickened on the SNP, that somehow they also abandon their beliefs.

The SNP is not independence, and independence is not the SNP. The SNP would like us to think that’s the case, as that tactic has kept it in power for plenty of years. However, many Yes voters have cottoned on to that charade, and realise independence is much bigger than a mere political party.

Evidently, the SNP is today the main - the only - political vehicle for independence. Yet, this is where the conversation with that high-ranking civil servant got interesting. With some trepidation we turned our attention to what Irish history tells us about constitutional change.

Now, I’m Irish - and I’m also a veteran reporter on political violence in Ulster - so any talk of Scotland following Ireland’s path to independence fills me with horror and anger. All I see is blood when I hear that. We’ve had leading Yes figures make the most stupid and inflammatory comments in this regard.

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However, the civil servant was clear that they weren’t talking about violence or extremism when it comes to Scotland. Rather they were referring to the history of the Home Rule movement and its enduring support despite the collapse of its main political vehicle the Irish Parliamentary Party (IPP).

Without rehearsing a complicated history lesson, by the late 1880s Charles Stewart Parnell, the IPP leader, was a dominant figure in British politics, much like Nicola Sturgeon or Alex Salmond before her.

Then scandal destroyed him. Effectively, as the civil servant noted: “The political conditions to deliver Irish Home Rule were gone, but the support doesn’t fade away.”

In fact, support gathers momentum. Sinn Fein rises. The War of Independence begins. The rest is history. Very bloody history.

Klaxon: Scotland won’t follow that path. I know that. The civil servant knows that, and neither of us are saying anything even remotely close to that. Ireland’s history is Ireland’s history. Scotland’s history - and future - is its own.

The Herald: Could Scotland's independence movement have the same longevity as Ireland's, with a peaceful successful outcome?Could Scotland's independence movement have the same longevity as Ireland's, with a peaceful successful outcome? (Image: Newsuest)

The civil servant summed up the Irish-Scottish comparison perfectly: “What this shows is that the collapse of the main political vehicle for independence doesn’t mean anything in the long term. In the long term, what matters is support for independence, not the health of the political vehicle to deliver it.”

So let’s kibosh all nonsense of aggressive Scottish separatism, and address a much more likely political future. We’re going to get a Labour government, for maybe two terms. But as everyone knows, the Tories will be back eventually. Probably by 2034.

By then, the SNP may have rejuvenated itself, or be dead like the IPP and replaced by another political vehicle. Not for a minute am I suggesting Alex Salmond’s Alba. Any new political vehicle would have to be moderate, offer wide social appeal, and not pander to a hardline fringe.

The civil servant pointed out that as Labour is inheriting a shattered economy and ruined public services, come the early 2030s the NHS on both sides of the Border will likely be in a state of collapse, and the “Great British state pension not what it once was”.

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Demographics will also change, the civil servant pointed out. Put brutally, young Yes supporters will be voting, and old No voters will be dying. Twenty years will have passed since 2014, leaving the "once in a generation" argument dead as well.

So, you’d have a hefty slice of the Scottish electorate sickened by a Labour Party they put their hopes in, an economy even deeper in the dirt, the Tories back in power, a pumped-up Yes movement, and the key reason not to hold a referendum - "once in a generation" - rendered meaningless.

“What’s implausible about that scenario?” the civil servant asked.

Nothing.

Perhaps then, the best outcome for the Yes movement is defeat for the SNP. The party isn't going to lead the nation to independence anytime soon. But taking the long view of history, there’s a feeling independence has a growing sense of inevitability behind it.