UNTIL the end of 2008, or thereabouts, "Scotland in Europe" was one of the SNP's more reliable slogans.

Before Ireland's banks bankrupted their country, before the Greek economy became a smouldering ruin, before financial institutions born in Edinburgh fell into disgrace, the phrase answered a lot of questions.

Chiefly, it meant a small, independent country need not be alone in world. It suggested Scotland could dissolve its relationship with the United Kingdom safe in the knowledge that something bigger and better awaited. Nervous voters could rest easy. A place among the nations of Europe would be reclaimed. And no harm done.

Things, it is safe to say, have become a little more complicated. These days the SNP, once enamoured of the euro, proposes a currency union with imperial sterling and the protection of England's central bank. It struggles to answer questions, most of them fatuous, on an independent Scotland's legal right to continuing membership of the European Union. Yet under Alex Salmond's leadership the party remains committed to its old slogan.

This makes the SNP a notable exception in the political wars of these islands. Euroscepticism is all the rage, especially among those who enjoy a good rage. Since David Cameron delivered a baroque speech full of qualifications, contradictions and unanswered questions last week, the promise of an "in/out" all-British referendum on Europe has bedazzled the political classes.

Those most dazzled are most certain of the answer, come the glorious day. Europe will submit to Britain's demands, or Britain will be off, back to the sceptred isle. The delighted Tory sceptics who crowded the TV studios after Cameron's speech had that old war-time David Low cartoon in their heads. You might remember. The Tommy stands at the stormy Channel's edge, shaking his fist at the Luftwaffe. The caption reads: "Very well, alone."

Which is nice, if that's your taste. Where does it leave the SNP? Well placed, if you believe the party. Salmond, reasonably enough, mocked Cameron for his strange choice of tactics, his fear of UKIP, and his lack of logic. On Thursday, the First Minister wondered at all the fuss over an independent Scotland's right to EU membership when Tories were "heading for the exits", and likely to take Scottish voters out of Europe with them.

Salmond spoke like a man sensing a political advantage. The SNP issued a press release, indeed, claiming the cross-party Better Together anti-independence campaign had been "impaled by its own arguments" thanks to Cameron. Alistair Darling, chairing Better Together, had claimed repeatedly that "one of the key benefits of Scotland being part of the United Kingdom is its place in the European Union". Cameron had made a nonsense of that.

Darling has certainly made such claims. His own party has, meanwhile, failed to rule out the possibility that it might "one day" stage a euro-referendum of its own. The Prime Minister alleges that he wants Britain to remain within the EU no matter what, but everyone knows – or thinks they know – what his speech portends. The SNP, in the words of Angus Robertson MP, meanwhile continue to offer "a strong voice in Europe with independence".

Is that a vote-winner? More to the point, is it a referendum winner? The SNP is acting in the belief that Cameron has delivered a gift by attempting to appease his eurosceptic wing and placate an English public hostile to all things "Brussels". For that to be case, wouldn't Scots have to be dedicated Europhiles?

The evidence is thin. Which is to say, the evidence is hard to come by. When it comes to European matters, surveys of Scottish opinion tend to be tacked on to UK polls, and involve samples of 160-odd. These, though, are consistent: Scots are only marginally less likely, by a matter of five to six points, to want out of Europe than the europhobic English. The difference can mostly be explained by the presence of SNP supporters. It seems we are not yet the new Europeans of Nationalist dreams.

On Thursday, at First Minister's Questions, the Scottish Tory leader Ruth Davidson attempted to taunt Salmond with this apparent truth, demanding to know whether he would offer an in/out European referendum of his own in the event of independence. She already knew the answer. "Vote for the UK, you have a chance of your say on Europe," Davidson said. "Vote independence, and he's telling you to pipe down and leave it up to him."

Quite why a pro-European such as Salmond would follow in Cameron's eccentric path was a question that did not detain the Tory. Instead, she was probably thinking of a YouGov poll from last October. This showed that while 48% of respondents across the UK wanted out of the EU, only 31% would choose to stay the course. Scotland was a little different: 43% would remain Europeans, but fully 42% backed EU withdrawal. Hence Davidson's taunts, which happened – by pure coincidence – to echo that morning's Scottish Daily Mail.

So how does it help the SNP to remain staunch Europeans? Principle has something to do with it. One old question often asked of Nationalists involves the nature of independence, and what they mean by it. Why end one political and economic union (the UK), just to join another (the EU)? Both involve a loss of sovereignty, and therefore independence. Both unions are afflicted by democratic deficits. Isn't our old friend anti-Englishness the only motive?

Smarter Nationalists respond that the EU offers much the better deal. The common fisheries policy (CFP), for one example, is crucial to Scotland. It is also a shambles. So why should negotiations be led invariably by London ministers rather than representatives of an independent Scotland? The argument can be applied to a host of other issues. Better to be represented on the Council of Ministers than wait for Whitehall to call. Besides, Scotland is historically, even culturally, a European nation.

It is possible, in any case, that all the sceptics are mistaken, and not for the first time. It may be that Cameron gave his desperate speech for nothing. When YouGov polled again on January 17 and January 18, it found a strange change of heart among voters. Across the UK, 40% wished to stay in the EU against 34% supporting withdrawal. The Scottish figure was 45% to 31%. The poll might have been a rogue. If it wasn't, Salmond is playing to the gallery.

He needn't be too subtle, however. There is another fact of Scottish life that trumps all talk of Eurosceptics and Europhiles. The point is not simply that a prime minister gave a speech with a post-dated promise of an in/out referendum on EU membership. The point is that a Tory prime minister gave the speech. The ultimate effect, as the First Minister no doubt calculates, is of a Conservative Party with a single Scottish MP deciding Scotland's future in the world.

We may be for or against Europe. If the latest Scottish Social Attitudes Survey is accurate, we may be fast withdrawing support for independence, with fewer than one-quarter reported in favour. But in Scotland, for a generation, there has existed a settled will. If the Tories want it, we're not buying. Last week, that became Salmond's European policy.