AS we now move tentatively towards the next General Election – or should that be “de facto” Scottish referendum? – it could be that the landmark Indyref2 ruling by the UK Supreme Court could signal the beginning of the end of Nicola Sturgeon’s time as First Minister.

Of course, every Scottish election in recent memory has had the constitutional question at its heart.

But Ms Sturgeon’s determination to make the next UK poll solely about independence, and her belief that an SNP majority – or, rather, a pro-independence majority – should trigger talks with the UK Government about ending the Union, pushes things into a different dimension.

A Channel 4 poll suggested that 51% of Scots would vote SNP at the next General Election if a victory for the party could lead to Scottish independence; 33% said they would not, while 16% said they didn’t know.

Yet last month another snapshot said that only 32% of Scottish voters would support a general election being used to decide Scotland’s future, with 58% opposing such a move and 10% not knowing.

The political temperature is always high at a general election but trying to turn it into a Yes-No campaign would threaten to raise it to boiling point.

Getting a 50%-plus-one vote is a very high bar. For that reason, the SNP at its special conference next year will doubtless make it clear that Scottish Green and even Alba votes will be included in the pro-independence total. So, Ms Sturgeon would effectively be attempting to set the terms of the ballot; although only those over 18 get the chance to vote in general elections.

Only once in any election has the pro-independence movement achieved this level of support; the famous SNP victory in the 2015 General Election, when the party got 50.0% of the vote and the Greens got 1.3%. Turn-out was 71%.

But if the Nationalists were to get their majority, arguing that this would be a green light for negotiations with Whitehall on independence, what would the new Prime Minister do? Would Rishi Sunak or Keir Starmer start their premiership by caving in to Ms Sturgeon’s demand to begin the process of breaking up Britain?

If they did, then their time in government would be completely overshadowed by one thing: they were the PM who lost the 315-year-old Union. I would suggest they would do anything to avoid such a prospect and “just say no”.

Which means that, apart from anything else in the run-in to the election, Unionist party leaders will condemn Ms Sturgeon for trying to “dictate” the election terms, but nonetheless resurrecting Project Fear about the economic dangers of Scotland going it alone.

If, in the face of most Scottish voters backing the pro-independence coalition, the new PM were to double down, then he would be under intensifying political pressure from Nationalists north of the border and, possibly, others south of it.

Indeed, the FM’s hope would be the pressure would become so great as to be irresistible. If Ms Sturgeon secured her victory, it would, to a great degree, be based on an irony; that the Conservatives and their allies by achieving Brexit – Britain’s independence from the EU – had created the catalyst which secured independence for Scotland.

But the biggest threat to the Nationalist nirvana is not likely to come from the Conservatives in a de facto referendum but from a revived Labour Party; or rather, from how Scots might perceive how well Labour could do at the General Election.

If opinion polls in the run-in to the 2024 vote showed Mr Starmer was heading for a landslide victory, it might concentrate the minds of wavering Scottish voters, who more than anything want the Tories out of power rather than opting for the risky uncertainties of full independence.

Indeed, Labour will be promising more devolved powers to Scotland in a changed constitution that will include abolishing the House of Lords and, possibly, whisper it, a hint of closer ties with the EU.

As ever, the delicate art of calibrating your election pitch not to scare the horses too much will be crucial.

So, between now and polling day expect the SNP rhetoric against Labour to harden, particularly as Mr Starmer and his colleagues make clear for those wanting to a) get rid of the Tories and b) save the Union, there is only one choice – and it’s not voting Conservative.

However, consider also what would happen if the Nationalists didn’t get the majority they so passionately desire.

Humiliating defeat would prove to be Ms Sturgeon’s last big gamble, resulting in her departure from Bute House. It could also result in a Quebec-style setback for the Scottish independence cause.

Keith Brown, the SNP’s deputy leader, was confident that Ms Sturgeon would lead the party into the General Election, telling BBC’s Newsnight: “I think yes.” He then suggested that she might “quite possibly” lead it into the 2026 Holyrood poll, before adding a gentle note of uncertainty, saying: “I certainly hope so.”

Of course, if the FM were to get that pro-independence majority in 2024 and if the UK Government conceded the point and began talks on Scotland leaving the Union, the idea that she would stand down and not lead the Nationalists into the first election of an independent nation and thus, in all probability, become Scotland’s first Prime Minister, is unthinkable.

Ms Sturgeon has already dropped into the public consciousness that her time at the top is limited, which makes you question how confident she really is about achieving her independence goal. Indeed in August the SNP leader declared: “The world is my oyster.”

There has been talk at Westminster that she has been eyeing an international job, possibly at the United Nations in the field of human rights. In such a scenario, her chief opponent in the battle over Scottish democracy – the Prime Minister – could greatly help the outgoing FM by privately putting in a good word for her within international diplomatic circles.

Now that would be the irony of ironies. But, then again, politics is often full of surprises.