ONE of the most remarkable aspects of the aftermath of September’s referendum was the speed with which political expediency overtook any concerns with securing Scotland’s place in the Union.

“Please don’t go” David Cameron – and Eddie Izzard – pleaded before the vote. Yet almost as soon as the result was in, the Conservative leader was tethering more powers for Holyrood to a deal on English Voters for English Laws.

The failure of Unionism to “win the peace” continued into the Smith Commission. Rather than asking what Holyrood actually needed to work best for Scotland, party leaders produced an inherently unstable compromise based on what each was willing to sacrifice.

Now it looks as if the UK’s political leaders – aided by a pliant press – are competing in a bizarre form of electoral hari kari: alienate as many Scots as much as possible, particularly those minded to vote nationalist.

So we had Allan Massie in this weekend’s Mail on Sunday comparing the SNP to the East German Stasi (obviously), the Sun on Sunday warning of a “doomsday alliance” between the SNP and Labour; Max Hastings, on a similar riff, wailing about Nicola Sturgeon being “red in tooth and claw” (wait until they tell Jim Sillars, he’ll be made up).

Even the normally sure-footed Guardian cartoonist Steve Bell went off-piste with a sketch featuring Salmond, Sturgeon and a commitment to “incest and country dancing”. Punching up, really Steve?

The stream of opprobrium runs straight from a central tenet of the current General Election campaign in England: that Scotland – and Scottish votes and the SNP – deciding a UK General Election is an abomination, a bizarre perversion of political values.

“How can the SNP be part of a Westminster government?” wail commentators of all shades, seemingly oblivious to the fact that this is exactly what political union means.

A seat at the table, if that’s what voters decide.

David Cameron, so animated by the prospect of losing Scotland six months ago, has basically declared open season on Scotland and Scottish voters, eager to depict the SNP and Labour as the thin edge of some imaginary red wedge.

In the latest Tory advert – designed by M&C Saachi who worked on that incredibly successful Better Together campaign – a sombre-faced Alex Salmond looks down at a diminutive Ed Miliband, the Labour leader safely ensconced in his jacket pocket. Subtle it ain’t. (Although, perhaps we should be grateful that at least Sinn Fein’s Gerry Adams isn’t swinging off Alex Salmond’s tie. That was the previous Conservative poster.)

“Be afraid, English voters”, the subliminals scream loud, “the bogeyman is coming”. From Linlithgow, via Gordon.

The Tory move is a cynical one; Shire voters dislike Salmond. Bundle him up with “Red Ed” and you’ve a potent combination with which to coax would-be switherers back into the fold. That the Conservatives have practically nothing to lose in electoral terms in Scotland makes the cynicism easier to sell in Tory HQ.

Nothing to lose, that is, except the Union.

And as with all things in British politics, where one arm of the duopoly moves, the other must follow. Labour can hardly decry Scots as Stasi-loving heathens – they need Scottish voters, badly – but they can pile atop the notion that any deal with the SNP is a deal with the devil. Nicola Sturgeon as Nick Griffin. Or, as Labour MP David Hamilton described her at Labour’s spring conference on Saturday, “the wee lass with the tin helmet on”.

Poll after poll shows many Scots voters want an SNP-Labour coalition. But Ed Miliband prevaricates, worried on the one hand about appearing “soft” on nationalism or, on the other, angering his own Scottish MPs as they desperately flail around to save their seats.

Remarkably it seems as if almost nobody from Labour or the Tories in Scotland can see the fallacy of pathologising Scottish voters and the party that 45 per cent of them voted for at Holyrood in 2011.

The Conservatives see only short-term political gain. Why else would deputy leader Jackson Carlaw yesterday jump on an unattributed magazine quote to proclaim the SNP could run as Labour’s Scottish wing, with the two parties forming a “permanent alliance” at Westminster. “It’s incredible,” the normally quite sane Carlaw fumed, “to think this suggestion could lead to either the SNP or Labour agreeing not to field candidates in certain areas to boost the other’s vote.” Yes, it is incredible, because it’s not going to happen.

Meanwhile reports suggest that on the doorsteps individual Scottish Labour MPs are adopting a “hardline” stance (“hardline” as in Stasi?), telling Scottish voters that they definitely will not do a deal with the SNP. Unionist parties have plenty to aim kicks at the SNP with – ID databases, Police Scotland, local government funding – but they have chosen to put the boot into Jock instead.

It is a strategy that could backfire, badly.

The more Scottish voters are told that their electoral preferences are invalid – or worse – the more they could come to believe that Westminster, and the Union it supports, is not for them at all.