Nicola Sturgeon’s descent from stateswoman to national laughing stock was a slow but steady process.

When she succeeded the late Alex Salmond as First Minister in 2014, she presented herself as a unifying figure, keen to heal division caused by the independence referendum campaign.

By the time she left office eight-and-a-half years later, Ms Sturgeon had become the most polarising figure in the history of devolution.

Her fall from popularity was accompanied by her obsession with staging a second independence referendum.

Despite having no authority to run Indyref2, Ms Sturgeon repeatedly promised her supporters to prepare for another vote on the constitution. In elections to both Westminster and Holyrood, she urged voters to back the SNP in order to secure another referendum even though she couldn’t give them one.

Countless times, the former First Minister marched Scottish Nationalists halfway up the hill only to march them back down again.

By the time she announced her resignation three years ago, Ms Sturgeon had run out of road on the independence question.

Years of overpromising, bashing into her inability to deliver, left once-devoted supporters feeling betrayed.

Add to this fixation Ms Sturgeon’s second obsession of gender ideology and you have the perfect poison to end a political career, a cyanide pill that kills credibility.

All of this being so, it’s a surprise that First Minister John Swinney seems currently to be shaping his own political strategy on his predecessor’s.

The SNP’s manifesto for May 7’s Holyrood election tells voters that a vote for the party is a vote for an independence referendum.

If the Nationalists win a majority, as they did 15 years ago, there would ‘based on the 2011 precedent’ be a ‘mandate for the transfer of powers to the Scottish parliament to enable an independence referendum to be held’. Interviewed in his campaign battle bus, the First Minister expanded upon this claim.

The SNP was, he said, very close to winning Scottish independence.

Mr Swinney said that, if a referendum followed on the same timetable as before and, as he expected, the Nationalists won, the process of separation from the United Kingdom would take 18 months, making Scotland independent by 2030.

At this point, Mr Swinney – who was planning to retire from politics until Humza Yousaf blew up his 13-month-long First Ministership in 2024 – would stand to be Prime Minister of this new nation.

Anyone awaiting the result of next month’s election before making a judgement on the First Minister’s words, look away now. I have a spoiler.

It was all the stuff of fantasy.

One can imagine the skirl of the pipes in the First Minister’s head as he spun this yarn of himself as the beloved father of the nation. Perhaps he imagined statues, a library named in his honour, a place in the history books.

The truth – the chiel that winna ding no matter how hard Mr Swinney tries dinging it – is that what happened in 2011 is irrelevant.

There will be no referendum in 2028, or at any other point during the next session of the Scottish parliament, something the First Minister knows fine and well.

Just as Ms Sturgeon did so tediously often, Mr Swinney is promising his supporters a referendum that won’t happen.

The authority to stage a vote on the constitution lies with the UK Government, a fact confirmed by the Supreme Court when Ms Sturgeon tried to introduce legislation for Indyref2 in 2022.

Nothing has changed since then and nor will anything – not even an SNP majority next month – change for the foreseeable future.

The First Minister’s confident words betray his weakness. The promise of a referendum he can’t run is a pitiful plea to the SNP’s core vote, to the blood and soil Nationalists entirely untroubled by the party’s failings across a wide range of policy areas.

The First Minister has put the fantasy of a second independence referendum front and centre of his campaign because, having long since given up the pretence of caring about the priorities of the pro-UK majority, his focus is now on appeasing those SNP voters who have not walked away after a range of triggers, from the party’s failed stewardship of the NHS to dark mutterings of a plot by former allies to bring down the late Alex Salmond.

The SNP may be on course to win next month’s election but recent polls show support for the party has fallen by 7 per cent across Scotland’s constituencies since 2021. Over the same period, the proportion of Scots who intend to support the Nationalists in the second, regional vote has dropped by eight points.

The days when the SNP vote included a substantial number of Unionists willing to support the party on the grounds of competence have long passed.

Mr Swinney, once a model of Nationalist gradualism, is now an ‘independence now!’ fundamentalist.

Where, I wonder, does the First Minister intend to take this line of argument after the election?

Is this simply a desperate short-term attempt to shore up weakening SNP support or does he plan to spend the next five years obsessing over the issue, making repeated claims of a mandate for a referendum, continually promising a plebiscite he has no power to deliver?

The worst of all this is that John Swinney and his advisers know the SNP’s manifesto lines about a referendum following a majority for the party are absolute bunk. The cynicism required to have published them is, in its way, impressive.

The pollsters on whose findings Mr Swinney now bases his prediction of SNP victory next month also tell us that a second independence referendum is far from a priority for the majority of Scots who, instead, believe the focus of the government should be on the cost-of- living crisis, the NHS, and schools.

The minority of Scots who, it seems likely, will return Mr Swinney to power next month are fired up by the prospect of a second referendum. How is the First Minister going to explain away to his supporters his inability to deliver on that promise, regardless of the election result?

Will he come clean with them about that reality and then focus his attention on the issues of most concern to the majority of Scots or will he continue to agitate over a referendum demanded only by a minority?

Does John Swinney have it in him to be a leader for all Scots or is he nothing more than a less charismatic version of what’s come before? Is he a statesman or a Nicola Sturgeon tribute act, playing to a half-full house at Pontins on a wet Wednesday afternoon?

Once the former First Minister led supporters to believe she could deliver a second referendum, she couldn’t let up. She was trapped in that lie.

Eventually, reality caught up with Nicola Sturgeon and brought her crashing down.

If John Swinney maintains the pretence he can give his supporters another independence referendum, he faces the same fate. And he will richly deserve it.