SO, Scotland – in or out of the euro?

It might seem a daft question when the very future of the European single currency is in doubt. But that hasn't stopped people asking it. Danny Alexander, the UK Treasury Secretary, in a speech on Friday demanded to know whether Scotland would be in or out, saying that the "deafening silence" from the SNP on the euro was "deeply damaging" to Scotland's economy. Margaret Curran MP, Labour's shadow scottish secretary, weighed in pointing out that "if a separate Scotland did use sterling, we would be in the weakened position of using a currency over which we had given up all influence and control".

She has a point. How could it be in Scotland's national interest to remain in a sterling currency union which is shaped in the interest of the southeast of England? Mind you, that is rather the case with Scotland at the present time, as the Nationalists see it. They regard keeping the pound as a temporary measure until such time as Scotland can have a referendum on the euro. At least, that was the line before the Great Split. The extraordinary events of the past few days mean that the whole debate about Europe has been turned on its head.

David Cameron's decision to use his veto in Europe to protect the bankers of the City of London from financial regulation by Europe has altered the course of history – though no-one is quite sure yet in what direction. In the early hours of Friday morning, Britain showed its hand; and Europe called its bluff. Rather than abandon a "Robin Hood" tax on financial transactions, and drop other measures to curb the excesses of investment bankers, Europe effectively showed Britain the door. And David Cameron walked straight out of it. Britain remains a member of the European Union, of course, but without any power or influence over what happens to it. Sounds familiar, doesn't it?

Britain is now more remote from the core of Europe than at any time since the referendum on Europe 36 years ago. There is a momentum towards disengagement that looks unstoppable. David Cameron will now be under intense pressure from the 100 or so eurosceptic Tory MPs who are demanding that he hold a referendum on renegotiating British membership – a euphemism for detaching Britain from the European Union altogether. The PM promised he would call one if there were any significant changes to the treaties or to Britain's relationship with the EU. There are profoundly significant changes taking place and that suggests that a referendum will be extremely hard to avoid.

This poses interesting questions for Alexander. There has also been a deafening silence from the pro-European Liberal Democrats in the coalition over the prospect of Britain effectively leaving Europe. David Cameron has not just rejected the eurozone, he has taken this country to the outer fringe of Europe, where he will reside in splendid isolation. Even the Hungarian leader, Viktor Orban – who has recently established what are effectively compulsory labour camps, which some have dubbed the "Goulash Archipelago" to deal with the unemployed – has balked at the prospect of being on the margins after initially signalling his support for Cameron's stance. I can't see Nick Clegg – lifelong supporter, not only of the European Union, but also of the euro – being able to put up with the solitude for long.

If David Cameron holds a referendum on renegotiating British membership of the EU, the Coalition partnership between the Conservatives and the Liberal Democrats will be over. It may be over anyway, because the consequences of isolation in Europe will place intense strain on the Liberal Democrats.

The City of London may be laughing all the way to the bank, but British manufacturing industry is desperately worried about Britain excluding itself from decision-making in the European single market. Even Margaret Thatcher, the godmother of euroscepticism, always insisted that Britain had to be represented in Europe, and that the "empty chair" policy meant UK interests going by default. Nicolas Sarkozy has made absolutely clear that Britain cannot remain as a non-member of the club telling it what to do. Britain is now the Iceland of Europe – the most highly indebted country in the world with a delinquent banking sector – in self-imposed isolation. Where will Scotland stand on that?

It seems plain to me that Scotland's interests may no longer lie with sticking with the pound if that means being excluded from Europe.

The SNP always said that Scotland should have a "seat at the top table"; now it doesn't have a seat in the building because the UK has decided to head for the exit. In such circumstances, an independent Scotland might listen with interest to overtures from the rest of the European Union to become an independent nation at the heart of Europe – now that England has made its excuses and left.

The idea that Scotland would be denied entry to Europe, even as England leaves it, is revealed as unalloyed nonsense. In its present mood, there's nothing Europe would like more than to see the UK disintegrate and for Scotland to join the euro.

I am pretty sure that Scotland would be given membership at a very reasonable rate. The new country would also be offered generous financial incentives, possibly even a derogation on corporation tax, to smooth its entry.

And as a petro-currency, Scotland might benefit considerably, because currencies based on natural resources such as oil have a habit of appreciating rapidly, thus making exports uncompetitive. Linked, at a favourable rate, to the euro, Scotland would not face that problem.

Danny Alexander's suggestion that an independent Scotland would become one of the "poor men of Europe" suffering permanent deflation and debt crises is as economically illiterate as it is offensive. Scotland would more likely become one of the many prosperous small states of northern Europe, joining countries such as Holland and Finland.

Assuming the European Union survives, that is. Given the current state of confusion it is perhaps facile to speculate about any future for the euro. But what is not in doubt is that Britain is on its way out, and that cannot but have profound implications for Scotland. As Der Spiegel put it: "Auf wiedersehen, England."