The Scottish Tories are today wildly celebrating the news that the Supreme Court has ruled that the UK government does not need to consult the Scottish Parliament before triggering Article 50 and exiting the European Union. What is considerably less clear is why they are celebrating, as opposed to drowning their sorrows.

Only the blink of an eye has passed since they invested huge political capital in establishing a narrative that the notorious "Vow" - which played such a decisive role in persuading Scotland to narrowly reject independence in 2014 - had been delivered in full, thus removing any possible justification for a second independence referendum before the fabled "generation" had passed.

What the Supreme Court ruling effectively does is publicly and objectively confirm for the first time that a key part of The Vow, which undertook that the Scottish Parliament would become a "permanent" institution, was a confidence trick.

With an audacious display of contempt for the Scottish electorate, the UK government's lawyer went before the court and openly boasted about how words had been inserted into the Scotland Act 2016 to ensure that the supposed legal enshrining of the Sewel Convention, which ostensibly ensures that no powers can be stripped from the Scottish Parliament without its consent, had no actual legal effect whatever.

That the court had little option but to accept that dismal argument is no great surprise. That the court passed no comment on the UK government's sheer cynicism in deliberately crafting a self-sabotaging piece of legislation is rather more extraordinary.

Rest assured that many people who voted 'No' in 2014, having truly bought into the promises that the UK was about to be transformed into something approaching a federal state, do think it's distinctly odd that Scotland's constitutional status has not been enhanced at all. What died today is not merely the illusion that The Vow was delivered, but also the lingering faith that the spirit of The Vow could somehow be kept alive and made more concrete at a later date.

It's become abundantly clear that the political and legal culture of the UK is simply incapable of accommodating Scottish distinctiveness in such a way as to actually give Scotland an institutional say over the destiny of the political state it is part of. In the absence of a willingness to accept that, a federal or quasi-federal UK is by definition a non-starter.

Huge chunks of the No campaign's pitch to the electorate have been comprehensively discredited

Even before today, the Scottish government already had an immaculate case for calling a second independence referendum, which now seems very likely to be held in the autumn of next year. The SNP were successfully elected in May on a manifesto which explicitly claimed the right to hold another referendum if there was a material change in circumstances, and used Scotland being dragged out of the EU against its will as an example.

But the timely confirmation that The Vow was a sham very helpfully gold-plates the case for the question of independence to be revisited. Huge chunks of the No campaign's pitch to the electorate have been comprehensively discredited, thus lending an increasingly hollow ring to the daily insistence from unionist politicians that Scotland expects Nicola Sturgeon to rule out a referendum.

The irony is that if the Supreme Court had ruled the other way, a second indyref would genuinely have looked further away at a stroke. With a statutory right to impede Article 50, Scotland would have had enough leverage to force Theresa May into a form of Brexit that met Nicola Sturgeon's red lines.

Ms May might well have found that an accommodation was nowhere near as unpalatable as she had imagined, and as it would have been forced upon her by the courts, she wouldn't even have taken much of a hammering for it in the press. She would also have found to her relief that the casus belli for an indyref had vanished in a puff of smoke. A win-win outcome if ever there was one.

Instead, the polar opposite has happened, and yet the Scottish Tories do seem to be genuinely jubilant. When historians get around to tackling this mystery, I suspect the only possible verdict will be: "They got hopelessly caught up in a short-term political drama, and lost all sight of the bigger picture."

James Kelly is author of the Scottish pro-independence blog, SCOT goes POP! Voted one of the UK's top political bloggers, you can hear more from James on Twitter:@JamesKelly