There is a new phenomenon to be observed in British politics, not in the Southern, or Seoul, jurisdiction of this island but in the Pyongyang-oriented North Britain ruled by the Dear Leader Kim Il-Sturgeon. The SNP exhibits the phenomenon of triumphalist losers.

Scotland exudes a climate of separatist victory. The SNP urgently projects an image of relentless Nationalist advance, of a remorseless drift away from the United Kingdom, of an irreversible momentum towards independence. There has been, we are told, a major cultural shift. The SNP, lent added impetus by Brexit, is within a few years – at most – of dissolving the Union and forging a totally new un-British future, probably at the heart of a brilliantly prosperous, more tightly integrated EU.

That is the mythology the SNP is peddling. The reality is that the fantasists dancing in the streets festooned with saltire flags are increasingly divorced from reality. These are losers posing as winners.

They were winners once: that is how the triumphalist myth was created. When the SNP achieved minority government in 2007 that was a genuine political achievement. When it went on in 2011 to overthrow half a century of Labour hegemony in Scotland and attain majority government – within a devolved parliamentary settlement specifically designed to prevent the ascendancy of any one party – that was a seismic victory. Nobody could deny the SNP credit for that achievement.

Since then, however – subtly, slowly, but increasingly substantially – it has been downhill all the way. The SNP is in political landslip: it is its decline, not its rise, that is gathering momentum. This began in 2014 when it lost the independence referendum by the dismaying (to separatists) margin of 10 per cent.

When a political party whose sole raison d’être is independence loses the plebiscite on that issue it has fought to achieve for 80 years, no propagandist force on earth has the capability to persuade the public it is growing in strength and on course for victory. It tried to reclaim that narrative at the UK general election when, as a consolation prize, it swept the board at Westminster, but the SNP’s own propaganda has rendered Westminster less important and this victory left SNP MPs constitutionally impotent.

Then at this year’s Scottish general election the SNP lost its overall majority. Although it still managed to remain in office with the support of a ragbag of independents, in the face of such a patent reverse it was futile to claim irresistible momentum was carrying nationalism forward. Then the SNP was on the losing side in the EU referendum.

Due to lack of political acumen the SNP did not at first repine over Brexit. Indeed, substantial elements of the nationalist movement even welcomed it. They did so because of a further illusion they laboured under. They had persuaded themselves that, since Scotland supported Remain by a margin of 2-1, a UK-wide victory for Brexit would create a fissiparous divide across Britain that would lead to Scotland breaking with the rest of the United Kingdom and nestling within the bosom of Brussels.

This latest delusion ignored two major sets of factors. The first set was the absence of any mechanism for Scotland remaining within the EU, the need for it to exit the UK before spending years applying for EU membership, with four member states pledged to veto Scotland’s admission due to anti-separatist preoccupations of their own, the lack of any substitute for oil as an economic base and the requirement to enter the euro currency.

The second set of factors included the failure of the SNP to gain a “Brexit bounce”. That reaction did happen, on a scale so small as utterly to appal the SNP – a tiny majority for separatism in a few polls for just three weeks after the Brexit vote. Now the polls have reverted to an eight-point lead for Unionism. Scotland’s fiscal black hole is currently £14.8bn.

Post-Brexit Britain increasingly looks like a much safer bet than the disintegrating European Union. The euro, the migration crisis, the problems of the Italian and now German banks, the de facto semi-secession of the Visegrad states, increasingly resorting to domestic government by referendum even as Euro-federalists demand closer integration – the European project is imploding before our eyes.

Most recently the SNP’s triumphalist myth has taken a battering on a new front: parliamentary arithmetic. The SNP would have been defeated in the Scottish parliament recently, over its plans to allow local authorities to raise council tax by three per cent, had Scottish Labour leader Kezia Dugdale not failed to register her vote.

A few days later the SNP was unable to avoid its first parliamentary defeat, on NHS reforms. Governments that face defeat in parliament tend to do so with increasing frequency, compromising their entire programme of government.

So, to date, the SNP has lost a referendum on independence, lost its majority government, huffed and puffed impotently after being on the losing side in the Brexit referendum, been rebuffed by the EU and is now beginning to lose parliamentary votes. The triumphalist narrative of “inevitable” independence rings hollow from a party running out of steam and credibility. At last, the skids are under the SNP.