When – as is the case – about 40 per cent of the electorate in Scotland want to do something which is economically disastrous for the country I find I keep scratching my head wondering why.

Why does a sizeable minority of Scottish voters want Scotland to leave the UK?

I get the emotional arguments but it is not emotion which will create prosperity, run our hospitals and schools, pay for dignified care for the elderly and all the other things we want – it’s cash.

The economic reasons the nationalists put forward for separation seem to group into two broad categories.

First, they say leaving the European Union is a complete disaster and Scotland leaving the UK and rejoining the EU can undo that harm.

I agree the UK leaving the EU was, on balance, a mistake. Not so much because in a narrow sense we will be worse off but because the UK had the opportunity to be a leader in the EU and the chance to help shape Europe’s future as a collection of independent, economically and socially liberal countries co-operating together for the common good. That opportunity is now lost and Scotland does not have the weight to regain it.

However, what the nationalists would have us believe is that leaving the EU has been a disaster of almost biblical scale – no food in the supermarket (there was last night) and the army standing by to distribute supplies to a starving nation. All imaginary drivel.

What isn’t drivel though, and it is a point entirely lost on the nationalists, is that the adverse consequences of Scotland leaving the UK would be many times that of the impact of Brexit. A hard border with by far our biggest trading partner, a different currency in the short term and the euro in the long term – all complete economic lunacy. The damage to business, jobs, our tax base, our ability to pay for public services would be severe.

The second thrust to the nationalist economic argument is that the English, London, the Tories, Westminster etc. are holding us back and that somehow if released from this prison we could do much more. At its extreme this stream of thinking (if you can call it that) even holds that somehow we are subsidising the rest of the UK.

To say that there is negligible evidence to support any of this would be over-generous – it is in fact all utter nonsense but that is not the point. The point for the nationalists is that for every real fact – such as the fact that Scotland’s ability to spend on its public services is subsidised by payments from the UK – they put forward a fake fact, in this particular case that we subsidise the UK. This is a technique perfected by Donald Trump – if you don’t like the real facts just create some alternative ones of your own.

We get the usual nationalists’ claptrap about the outrage of being ruled by Westminster – the same outrage that those in Orkney could direct at Edinburgh but they don’t because Orcadians are not prone to whining. If you look past the bleating it’s just anti-democratic, anti-English nonsense. In all elections some geographic area doesn’t get the government they voted for – what is billed as an outrage is in fact entirely normal.

The mythical Tory austerity bogey is wheeled out again and again. The reality is that this Tory Government has borrowed on a staggering scale and passed a very fair share of the cash raised to Scotland to support our economy through Covid.

If only we were free this thread goes, we could invest more in all sorts of nice things – green, fair, diverse stuff we all apparently want. “Invest” is actually a codeword – it really means spend. Those who want Scotland to leave the UK delude themselves – and seek to delude the rest of us – that separation would open up a new era of increased state spending. The reality would be tragically different – austerity on such a scale as we have never experienced before.

The economic prospectus the SNP put before us in 2014, that all would be well as Scotland prospered in a sea of oil, has turned out to have been a dangerous fantasy. The new prospectus of half-truths and distortions is just the same and should be seen for the fake it is.

Guy Stenhouse is a Scottish financial sector veteran who wrote formerly as Pinstripe