Graeme Archer is a statistician and a former winner of the Orwell Prize for Political Blogging.

Suppose Salmond wins. We’ll poke around Douglas Carswell’s psyche in a moment – everyone else has had a go, including the man himself – but let’s start in Scotland. Maybe I’ll show that the two aren’t un-related (“not…unrelated” breaks one of Orwell’s language rules which I championed last week, but after Carswell I think a little inconsistency should be forgiven).

To my homeland:

‘The Unionist says, I am Scottish. Nevertheless I am also British, and value the Union with England, “our sister and our ally”, as Scott called her.’

The endpoint of a beautiful essay by the great Scottish novelist Allan Massie, just published by The Saltire Society. The essay is called “Nevertheless”, which Massie explains by reference to Muriel Spark:

‘“Nevertheless” was, she said, a very Scottish word, and what she called the “nevertheless principle” informed her writing.’

Throughout the referendum campaign, I’ve refused to accept that our nation of nations could be ripped apart. Salmond’s value proposition (“Be smaller, so that I can be bigger”) seems simply resistible.

Nevertheless, the latest polls show momentum for Yes, notwithstanding the mob violence displayed by the pro-independence, er, mob over the last few weeks (that cybernats are thugs in real life – this is a surprise to people?).

So, suppose Salmond wins. What then?

“Nevertheless, I am also British…” Nope! Perhaps the first visible changes in a post-UK Scotland would be felt within its artistic community. I noticed an irony while holding Massie’s essay: the cover art was produced by Alastair Gray.

Mr Gray is another great novelist (in my opinion), but not a Unionist. At the end of 2012, he wrote a deplorable essay which suggested it was possible to separate non-indigenous Scottish residents – English people, mostly – into “settlers” and “colonists.”

The essay has since been revised by its author, although it sounds as repellent to me as ever. His settler/colonist division remains: settlers are OK, because they appreciate Scotland’s “special culture” (obey the word of Pat Kane!); the colonists…well, the colonists are The Other. And therefore unwelcome.

Remind you of anyone?

“I was asked a question if a group of Romanian men moved in next to you, would you be concerned. If you lived in London I think you would be…I’m not demonising anybody.”

Settlers welcome (people who look and think like Nigel/Alastair). Colonists can bog off.

A polite word for this is nativism. It is not the same as insisting on common standards of behaviour. That is a fine, Tory thing (and I say so often – too often, maybe). But Alastair/Nigel, the Scottish/English nationalists, pick on some arbitrary characteristic – are you English? Romanian? – and demonise people who lack it.

This matters, because if Salmond wins, England won’t be ushering in Eternal Tory Rule. While English “settlers” in Scotland re-train themselves to speak like Rab C Nesbitt, south of the border we’ll be learning to mouth along with Miliband.

Which brings us to the man we’ll have to thank: Douglas Carswell. Mr Carswell will say, correctly, that it’s up to the electorate to choose their vote. In Clacton they will vote overwhelmingly for him.

But he hasn’t just finished off the Cameron government (I can see no path now to a Tory majority: it’s back to the 80s, through the looking-glass.) He’s unleashed something that I cannot believe (based on his writing) he won’t live to regret. In his interview with Conhome:

[A UKIP voter approaches Carswell]: “When you’ve got the National Health Service, let’s face it, you can’t pay for the influx of immigrants any longer.”

Carswell: “I don’t think that is the fundamental question.”

Supporter: “I’m not allowed to say these things. But I’m speaking what everyone else is saying.”

Carswell is about to be tribune for such views, the utterance of which cannot (“ting tong”!) come as a surprise to him. He could have resigned his seat and stood as an Independent for Brexit: he chose UKIP.

UKIP aren’t Tory in their approach to immigration (control it.) They’re…nativist. Would Carswell campaign under UKIP’s despicable posters? We must presume so. The Right of British politics is about to pull itself apart – because the anger of UKIP supporters is matched by the distaste their anger engenders in the stomachs of otherwise Tory-minded voters – and so pull away from a parliamentary majority, for ever.

And as for those things that UKIPers think they’re not allowed to say: we’ll hear little else from now on. Look at the snarl slipping from behind the (Scottish) nationalist mask, if you’d like a preview. It’s a different mask, north and south of the border, but the same destructive force damaging both countries (and therefore, at least for now, our country.)

My friend Chris Deerin called his latest piece, about the polarisation induced by separatist-nationalism, “There’s no such thing as monsters.” I agree with every word, other than the headline (this won’t come as a surprise to him). This polarising In/Out Yes/No Us/Them separatist-nationalism is a monster, powerful enough both to break up the UK and deliver decades of Left-wing government in England.

All monsters come to regret their lack of humanity (where did I hear that said, recently? Not in Chris’s piece, but he alludes to the fact). Of course Alex Salmond and Douglas Carswell aren’t monsters. But they’re feeding one. The same one. And the rest of us are going to have to live with the consequences, in what’s left of our nation of nations, when they’re done.