Most national leaders of an authoritarian persuasion have their own ’crossing the Rubicon’ moment.

For one-time democrat Robert Mugabe, it was the period in the early 2000s when he started defying court rulings in a successful effort to indefinitely extend his period in office.

For Theresa May, it was her decision last week to say ‘no’ to a request from the democratically-elected Scottish Parliament for a Section 30 order that would allow an independence referendum to take place on the same basis as the 2014 vote.

In so doing, she reversed more than four decades of British government policy, which since the days of Harold Wilson has been that Scotland can only remain part of the United Kingdom by consent. The exact mechanism by which Scotland is able to express its wishes on its own constitutional future has changed during that period - Margaret Thatcher always stated that if the SNP won a majority of Scottish seats at Westminster, that would in itself be a mandate for independence. By the time that target was actually met under David Cameron in 2015, it was felt that a referendum was the more appropriate way of securing a mandate. But the constant has been that Scotland has a clearly-understood democratic path to independence which it can take at a time of its choosing.

No more. The new Theresa May doctrine is that there is literally no way Scotland can express a view on its own future, until such time as the PM decides for her own reasons that she is ready. She makes no bones about the fact that the time may never come, and that a key strand of the democratic process in Scotland may remain indefinitely suspended.

From the moment Ms May made her announcement, the notion that Scotland is part of the UK by its own consent was converted from reality to fiction. The Scottish unionist politicians who have cheered this development in a knee-jerk fashion ought to step back and reflect on what they are actually lending their support to. This is not part of the legitimate democratic fight to thwart the SNP’s objective.

Now, it goes without saying that Ms May has a list of excuses as long as your arm to justify her outrageous decision, and each and every one of them is a sham. Most obviously, she says that Scotland has already decided to remain part of the UK. Even glossing over the fact that the 2014 decision was made on the demonstrably bogus basis that it would keep Scotland within the EU, Ms May’s argument is that of the would-be tyrant who wins one democratic election and says : “We don’t need any more elections. Not in five years, not in ten, not in twenty. That one was fine.”

She also argues there are various deficiencies in the mandate for a second independence referendum, either because of her hair-splitting objections to the wording of the SNP and Green manifestos, or because the SNP supposedly didn’t do well enough in the Scottish Parliament election last year.

Well, let’s just remind ourselves of what the result of that election was. The SNP received 46.5% of the constituency vote – that’s a bigger mandate than any UK government has received at a Westminster general election since 1966, more than five decades ago. There are very few governing parties anywhere in Western Europe, either at national or regional level, that can boast of stronger public support than the SNP. If it is to be seriously claimed that the Scottish government do not have a mandate to act, it’s murderously hard to think of a government anywhere that has a mandate to do anything. Certainly not the ‘majority’ Tory government in London, which was elected on the basis of just 37% of the UK-wide vote (and less than 15% of the Scottish vote).

As far as the contrived objections to manifesto wording are concerned, I would be interested to see what the reaction would be if Brussels were to say “sorry, chaps, a ‘t’ wasn’t correctly crossed in the Tory manifesto, so we’ll have to start overturning votes in the Westminster parliament”. Indeed, the very fact that Brussels wasn’t able to veto Britain’s second referendum on EU membership is a useful demonstration of the difference between a political union that respects national sovereignty and parliamentary democracy, and a political union that does not.

In the real world, though, the decision of the elected Scottish Parliament will prevail, no matter how loudly Theresa May stamps her feet. Nicola Sturgeon has numerous cards to play if Ms May remains intransigent, including a consultative referendum held without Westminster’s permission, or an early Holyrood election to establish an outright mandate for independence. The implied threat of either of those may be enough to force Ms May to the negotiating table.

But even after this stand-off has been long since resolved in Ms Sturgeon’s favour, one image will linger long in the memory – that of the defeated Scottish opposition leader Ruth Davidson being tasked with announcing what the elected Scottish government would not be allowed to do.

Nothing could better symbolise a truly farcical attempt to subvert democracy.

James Kelly's blog, Scot goes POP!, is among the most popular political blogs in the UK. He has also contributed to a number of newspapers and magazines.

You can check out the blog here or follow James on Twitter.

James has also written for us about why young Scots must vote for Sturgeon on June 8, the madness of King Trump, the crisis created by the Brexit legal challenge and why Scottish Labour care more about Corbyn than their country.

