Defeat at the next General Election. How can the SNP expect anything else? The party has been engulfed in scandal after scandal. It’s offered Scotland nothing but policy failure. It’s continually at war with itself. It’s prioritised the never-never land of independence above the here-and-now in a time of economic terror.

Gesture, dreams and rhetoric are the materials the SNP is made of, when the public wants action and honesty.

What a sad, sorry fall it is. But political inevitability has caught up with the SNP. If latest analysis is correct, Labour will take 22 seats at the next UK General Election in Scotland. At the last election, Labour took one. The SNP will take 20, losing 28.

In an astonishing inversion of the UK picture, the Scottish Tories will increase their vote, returning 11 MPs - rising by five. That’s how pitifully the SNP is performing. It's gifting seats to a dying party.

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Across Britain, it's predicted Labour will return 402 MPs, gaining a majority of 154. The Tories will win just 151 seats, losing more than 200 MPs.

Yet the SNP groundlings are shocked at the ruin facing their party. Why? It’s like Ridley Scott being surprised that historians find his Napoleon movie risible, when he’s filmed scenes of Bonaparte firing cannon at the Pyramids, an act which didn’t happen.

If you do something stupid - or many stupid things for that matter - people with a brain will notice and respond.

Perhaps the surprise within SNP ranks is half the problem. This party’s arrogance has been its defining feature for years. Instead of developing intelligent tactics to deal with Labour’s resurrection, its base scoffed and sneered. "Nobody will vote Red Tory" they hollered as each poll showed Labour inch ever forward until its lead over the SNP became inevitable.

The SNP’s problem has always been that it thinks it "is" Scotland. No other party, in the SNP imagination, represents Scotland. That was always going to pave a road to defeat.

So now the endbgame approacheth. And it approacheth in more ways than one. The SNP’s defeat at the next UK General Election will be bad for the Yes movement, but perhaps not as bad as the internal war that’s coming: Alex Salmond’s legal action against the Scottish Government.

The Cain and Abel story of the Salmond and Sturgeon factions will finally come to a conclusion. Someone will win - though in truth nobody will win. For if all sides believe in independence, the one casualty of this confrontation will be the Yes movement.

The notion of a harmonious Yes movement has been comically naive for years. Calls by Mr Salmond’s Alba Party for a "Scotland United" deal with the SNP - to bring the Yes movement together to fight for independence - are dust in the wind now.

Such calls were always bogus. Mr Salmond’s party did everything possible to undermine a creaking SNP. Now those calls can never be made again.

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Savvy members of the Yes movement know the game is up. In the letters pages of the pro-independence newspaper The National, readers are expressing their rage at Mr Salmond. One said of him: “You have almost certainly deprived me of any chance of seeing independence.”

It’s crisis both within and without: externally the SNP faces defeat at the hands of its old enemy Labour, and internally the Yes movement is about to tear itself to shreds … again.

In terms of electoral misery, the smart money must be on matters getting worse for the SNP. We’re still a long way off from polling day, and the graph only points downward. Who knows how bad it will get?

Indeed Finance Secretary Shona Robison seems inclined to dig the party’s grave even deeper. The public sector workforce will have to shrink due to funding pressures, she says.

Now, if this message of woe came from a party which had strained every damn sinew it had to improve the nation’s finances then maybe many of us could swallow such dire medicine. But when the message comes from a feckless party which has frittered away fortunes, it’s frankly intolerable.

The Herald: The Cain and Abel story of the Salmond and Sturgeon factions will finally come to a conclusionThe Cain and Abel story of the Salmond and Sturgeon factions will finally come to a conclusion (Image: Newsquest)

The recent delve into the Scottish Government’s finances by the Auditor General gives some indication of how pitifully the SNP has performed economically. Here’s one example: the total investment by the Scottish Government in Prestwick Airport has been £52.5 million. The value of Prestwick today: £11.6m.

We’re all sick of hearing about the ferries scandal, a failure which sums up the SNP: incapable of building a few ships in a maritime nation. But look at the figures: total investment in Ferguson Marine £237.5m. Value of Ferguson Marine today: £82.6m. Or there’s BiFab. Total investment £50.9m. Value: nil.

Then there was the shameful sale of Scotland’s assets through ScotWind - throwing the family silver at private investors. ScotWind made £750m for the nation. It could have made billions.

Now Scotland faces reduced staffing for public services and we’re told that ministers want to avoid compulsory redundancies.

How will this play into the SNP’s declining electoral fortunes? It will reap a whirlwind.

Of course, it can try, with some degree of fairness, to blame the Conservative Government. But it wasn’t the Tories who signed the ScotWind deal. Ferries aren’t the responsibility of Westminster.

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You cannot put all the blame on the big bad Tories in London, when you’ve been throwing cash around like a drunken sailor on shore leave.

So where does the SNP go from here? There are only two roads: policy or populism. Humza Yousaf can try to use what time remains to his government to draft policies which the public believe are fit for these hard times. But let’s be honest, neither he nor his cabinet are capable. And it’s too late.

That leaves populism: fomenting rage and getting dirty to try to stave off defeat. But Mr Yousaf doesn’t seem to have that in him, either, does he? And again, it’s too late. Times have changed, people have lost faith, the political pendulum has swung.

And so defeat at the next UK election is now inevitable. After that, the party goes into shell shock terrified at what comes next. For after defeat at Westminster, comes defeat at Holyrood, and then the party really is over.