POST-BREXIT Scotland sometimes seems like a nation of lost souls waiting for a second coming. No one in the Scottish Government has actually promised another referendum on independence, least of all First Minister Nicola Sturgeon. But the weight of expectation is such that if she doesn’t announce one at the SNP conference next week there will be a lot of very disappointed people.

It could also look like a considerable loss of face for Ms Sturgeon, who has spent six months promising that she “isn’t bluffing” about calling a referendum if Scotland is not guaranteed access to the European Single Market (ESM) after Brexit. Scotland, it is clear, will not be allowed continued membership of the ESM, or any special deal. And to rub it in, Theresa May has made clear that the Scotland Act itself is no longer fit for purpose post-Brexit.

But if a second referendum does happen, just what kind of campaign might it be? Unionist commentators forecast a more divisive and bitterly fought campaign than last time, and they may be right – but that’s only because, as the Scottish Police Federation made clear, the 2014 referendum was almost entirely peaceful, democratic and law-abiding. The only real disturbance was from the anger junkies on the internet. Not a single bullet was fired, nor a single punch thrown. The only projectile was a solitary egg hurled at the then Scottish Labour leader, Jim Murphy, while he was touring urban centres armed only with a soap box.

Compared with independence movements in places like Ireland or Eastern Europe, Scotland’s Yes campaign emerges as a uniquely good-natured, almost benign political insurgency. And long may that continue. Yet, the level of popular engagement with the independence campaign was huge: an unprecedented 97 per cent voter registration and an 85 per cent turnout on the day. Scots cared a great deal about the choice before them.

Reading the latest definitive account of the 2014 campaign, Debating Scotland edited by Professor Michael Keating, director of Edinburgh University’s Centre on Constitutional Change, I was reminded just what a odd independence campaign it really was. On the surface it appeared to be almost a single issue campaign about the future currency of an independent Scotland.

Yet, the American Declaration of Independence never mentioned currency, nor did Irish nationalists worry overmuch about credit ratings or sterlingisation. When the Baltic states declared their independence from the Soviet Union they weren’t remotely concerned about convertibility with the rouble (even though the International Monetary Fund argued that they should be).

Indeed, it’s arguable that the very attempt to forecast any future arrangements was futile because it was impossible to know the circumstances that would obtain when Scotland became fully independent. Insisting on currency union, as the SNP did, just allowed the UK Government to issue the killer declaration that, as George Osborne put it, “if Scotland walks away from the Union it walks away from the pound”.

Still more remarkable then that, having narrowed the campaign focus on to an issue on which it could not win, the independence movement almost succeeded. At any rate, Yes Scotland ran the Unionist Better Together far closer than anyone could have forecast when the campaign began. Forty-five per cent of voters, 1.6 million, opted for what experts from the IMF to the Institute for Fiscal Studies were forecasting would be a costly leap in the dark.

Even more surprising, as the Keating book makes clear, was that the vast majority of voters didn’t seem to be particularly motivated by independence or identity politics. Most Scots seemed to be in the middle range of “devo-max”, federalism, and more powers for Holyrood, and the economy dominated debate. Chauvinist sentiment was conspicuous by its absence. There was no obvious hatred of English people, precious little celebration of Scottish culture and almost no attempt to invoke the ghosts of Wallace, Bruce and the Scottish Wars of Independence.

The final remarkable characteristic of 2014 was that, after their defeat, the losers swept the board. SNP membership quintupled in the next 18 months; Labour lost 40 out of 41 Westminster in 2015 seats and the SNP now dominates politics at almost every level. Really, politics doesn’t get much stranger than this.

So will history repeat itself? Well, the economic arguments will still be relevant, especially given the collapse of oil revenues, but there won’t be a repeat of Project Fear. This for the obvious reason that it largely failed (and completely failed in the EU referendum). Most of the economic arguments have been debated to death.

This time, with Brexit, and the questions over Britain’s future trade and security, the uncertainty factor applies equally to the Unionist case as to the Yes campaign. There will be an equivalence of risk. Indeed, the argument for Scotland remaining in the EU may make independence appear the safer bet to some. Also, Scottish Labour will not be leading the campaign hand in hand with the Conservatives.

But the biggest difference will be sovereignty. As the Times columnist Melanie Phillips has made clear in an incendiary article, Brexit is about re-asserting British national sovereignty and recreating a unified and integrated UK. In fact, she comes close to saying that Scotland and Ireland never really existed as authentic countries and were “cultural phenomena rooted in romanticism and myth”. What she calls the “British Isles” is the only “authentic nation” and “secessionists” must not be allowed to destabilise it.

This is largely historical nonsense. The British Isles is a geographical not a political entity, and Scotland and Ireland were nations for centuries before the 1707 Union created Great Britain. Moreover, Scotland retained most of its national and institutional identity after union. Her thesis is is easily dismissed, but I think she has perhaps given us an important insight into the mind of the British establishment – at least the Brexit side of it. The idea of “British Empire 2.0” isn’t just a joke doing the rounds of Whitehall.

According to Liam Fox, Brexit is now explicitly about reviving the Commonwealth trading universe with Britain at its centre, as it was in the days of the British Empire in the 19th Century. This is an “anglophone” alternative to the EU. It requires a much more united UK, not least because a disintegration of the British state, or even a federal restructuring of it, would undermine the project to Make Britain Great Again.

This is a radically different context to 2014, when it was assumed by many that the UK was becoming federal by default, and also was destined to remain in the European Union. A second independence referendum – if it happens – will be largely competing questions of national sovereignty rather than comparative economics. Scots will be required to consider whether their destiny lies as an independent country in Europe or as a region of a monolithic UK. Brexit has made the national question truly national again.