What was it Alex Salmond said shortly after the referendum?

That everything had changed; changed utterly.

At the time it smacked of hubris, but not for the first time he showed an acute ability to forecast the lay of the political land and position himself - and more importantly - his party accordingly.

Loading article content

Since 19 September the SNP has sought to avoid getting squeezed, as it usually is, in a UK general election, and judging by the polls it's succeeded. Last week's survey by Lord Ashcroft brought to mind YouGov's polling during the referendum, an indication to the political classes that their vague inkling of a Nationalist surge was in fact real.

Normal electoral patterns have broken down and the standard "rules of the game" under which Scottish and UK politics are conducted are increasingly meaningless. This, to an extent, is a good thing: all political systems need a good boot up the backside on occasion, and May 2015 looks likely to be pretty painful.

So those are the electoral probabilities, but more interesting to me is why this has occurred. As ever, it has less to do with the SNP's prowess in government (it's been competent, sure, but can lay claim to few transformative policies, not least in terms of tackling inequality) or Labour's position on the ideological spectrum (business leaders spent last week attacking Ed Miliband, not Nicola Sturgeon), but a lot more to do with presentation.

The referendum has been skillfully recast as a straightforward struggle between good and evil, left and right, the masses and corporate elites, the SNP and everyone else. As the historian Colin Kidd put it recently, "the nationalists lost the referendum, but they won the narrative", and in modern politics whoever controls the terms of debate finds themselves in a pretty powerful position.

It has been fascinating to watch various London-based commentators make sense of it all. Writing a few days ago, the Guardian's Martin Kettle concluded that Labour's credibility in Scotland rested upon "whether it is a plausible government in waiting". If Scots believed Labour could form the next UK Government, he wrote, then "the Labour vote will remain reasonably solid".

That may once have been true - arguably it was in 2010 - but the Scottish political dynamic has moved well beyond that. Indeed, we've now reached a point where the SNP can say or do anything and a sizeable minority of the electorate will accept it as gospel, largely because that party is more trusted than any other.

So both the Labour Party and the UK Government, indeed Unionists in general, must now face the fact that no matter what they say or do in response, opinion in Scotland is unlikely to shift dramatically. And if the frequency of Scottish Labour press releases is an accurate measurement of panic, then I suspect those at Holyrood and John Smith House have already reached the same conclusion. Plans to co-opt the word "Yes" look desperate, as was reported yesterday, largely because they are.

Take Labour's oft-repeated warning that voting SNP will simply result in another Tory government: although essentially true, it no longer has any traction. Whoever forms the next UK government has to be the largest single party in the House of Commons, and the better the SNP does in Scotland then the less likely that is to be Labour. If, for example, the Nationalists take 40 seats in Scotland, then Ed Miliband will need to gain 88 constituencies in England.

That simply isn't going to happen, indeed no one I've spoken to recently (including Labour people) believe anyone other than the Conservatives will emerge as the largest party in terms of MPs. This means that the recent focus of most commentary, a Labour/SNP deal (formal or informal) is a bit of a red herring. Only very rarely has a party with fewer seats than its main rival formed a government, i.e. in 1923 and February 1974.

Which is why, as Iain Macwhirter wrote in yesterday's Sunday Herald, the SNP's decision to rule out unequivocally any deal with the Conservatives makes little sense. If the Nationalists genuinely want to maximise their influence in a "balanced" Parliament and hold, as Alex Salmond puts it, Unionist "feet to the fire", then such a stance reduces rather than increases their chances of doing so.

I can't help feeling, however, that this "no deal with the Tories" line is just that, a pre-election position the SNP feels it has to hold. Speaking to the Observer in December Mr Salmond was more pragmatic, saying that the SNP would look to squeeze concessions from a minority Conservative government on an issue-by-issue basis, for example securing Scotland an opt out should the rest of the UK choose to leave the European Union.

Here history is instructive. Back in February 1974 Scottish and UK politics was in similar flux: there was a hung Parliament, the SNP was surging and a referendum on Europe was likely the following year. Following the election Edward Heath secured fewer seats than Labour but gained more votes, and as the incumbent Prime Minister he had the first opportunity to form an administration.

Although his main focus was Jeremy Thorpe's Liberals, there were also informal back-channel discussions with the SNP's seven MPs regarding the recent Kilbrandon proposals for Scottish devolution, while in late 1976, by which point Jim Callaghan led a minority Labour government, Hamish Watt, the SNP MP for Banffshire, told an opposition Tory whip that "there was room for agreement between the SNP and the Conservatives". And as in 1974, any prospective deal hinged upon devolution.

History might well repeat itself. The well-oiled Whitehall machine is already contemplating various post-election scenarios, which by precedent involves informal discussions with opposition parties to gauge red lines and likely negotiating positions. Nicola Sturgeon will be in London again this Wednesday, as will her deputy John Swinney, and it's tempting to conclude that isn't just to make speeches and give television interviews.

U-turning on its no-deals-with-the-Tories position would be risky, but then the First Minister (not to forget her predecessor) has sufficient authority to pull it off. The quid pro quo would obviously have to be credible, and as in the 1970s it would likely involve devolution; Ms Sturgeon's line on EVEL (repeated yesterday) could even be interpreted as a pitch to the Conservatives, something to be negotiated away if they come up with the devo-max goods.

A political culture in flux tends to produce unexpected alliances. As a UK Government minister put it to me recently: "From our point of view, she [Ms Sturgeon] is someone who you can do business with." And what more important business is there than deciding who governs Britain in the wake of an indecisive general election?