Was Scotland a country or was it a nation? Growing up there I heard it referred to more often as the first – a great wee country, a bonnie country, sometimes a ghastly country. “Nation” was what nationalists called it: Scottish nationalists, that is – the British nationalism of the rest of us was a norm that went largely unarticulated and unremarked.

In some ways, the difference was only semantic. If being a nation meant having separate educational and legal systems, distinctive banknotes, a definite boundary, and a church and sports teams it could call its own, then Scotland had all of those. Still, the word “national” when it prefixed emergencies, economic indicators and political scandals implied that the nation in question was the United Kingdom – the notion that the UK comprised four virile national identities held together by a ghostly underlay of Britishness was some way in the future. Sometimes, in house-price bulletins and poverty indices, Scotland wasn’t even a country but a “region”, like the East Midlands. Beyond cultural and social markers, such as poetry and football, Scotland’s status was ambiguous, and for quite a long time only a minority of its citizens cared.

The trouble is that to redistribute wealth, a state needs to have it in the first place

For many people it was devolution that initiated the change. I have a memory of Peter Mandelson in Edinburgh in the late 1990s, either after the result of the devolution referendum or when the new Scottish parliament had its first session. “A nation once again,” he happily told a reporter, intentionally or accidentally referencing an early anthem of Irish nationalism (And then I prayed I yet might see / Our fetters rent in twain / And Ireland, long a province, be / A nation once again). It was surprising to hear an English politician, especially one as metropolitan as Mandelson, give such a jaunty opinion; because if Scotland was now definitely a nation rather than something mistier and less certain, why shouldn’t it be a nation state, like Ireland in the song?

Nicola Sturgeon, Scotland’s first minister: the case for self-government ‘transcends the issues of oil, of national wealth and balance sheets’. Photograph: Jeff J Mitchell/Getty Images

The Scottish National party, of course, thinks that it should be. It’s why the party exists. And yet it owes a good part of its recent success to ignoring the tenet of nationalism that says a nation deserves to be independent if its population can muster a strong, shared sense of identity. This is what the legal philosopher Neil MacCormick, the son of one of the SNP’s founders, John MacCormick, called “existential” nationalism – independence for its own sake – as opposed to the “utilitarian” nationalism that seeks sovereignty as the basis of social, economic and cultural change.

The late Stephen Maxwell, one of the SNP’s liveliest intellectuals, set out the utilitarian case in 1981 when he argued that the party needed to disregard “romantic” conceptions of nationhood and instead make an “unsentimental [appeal to] the social and economic interests of the Scottish people”, and particularly to the industrial working class, who had suffered most from Britain’s economic decline.

Alex Salmond was among the group of SNP members in the 1980s who held a similar view, though it wasn’t until 2012 that the party’s deputy leader, Nicola Sturgeon, compared the two kinds of nationalism in a significant speech written by Salmond’s policy director, Alex Bell. Sturgeon said that “the fact of nationhood or Scottish identity is not the motive force for independence”; nor did she think that independence was essential to preserve “our distinctive Scottish identity”.

In fact, she felt that feeling British, “with all of the shared social, family and cultural heritage that makes up such an identity”, should present no barrier to voting for independence, even though a successful outcome would mean the end of Britain as a political entity. Sturgeon had just been put in charge of the SNP’s referendum campaign. She promised that over the next two years the debate would focus on the question being asked across all mature western democracies: how to build a thriving but sustainable economy that benefits the many, not the few.

As for the real or imagined victimhood that has fuelled independence and separatist movements everywhere, Salmond wrote in the referendum’s consultation document that Scotland wasn’t oppressed and had “no need to be liberated”. Independence mattered because without it Scotland lacked “the powers to reach our potential”.

Four years after they were written, these equable statements now look even more remarkable than they seemed at the time; the Brexit campaign – the first significant eruption of modern English nationalism – was a disturbing populist storm by comparison.

Of course, the rank-and-file of the yes campaign didn’t always share the leadership’s avowed interpretation of nationalism, in which political calculation had a part: to win, the SNP needed to persuade wavering unionists that a big constitutional change was no social change at all. (As Salmond wrote: “Much of what Scotland will be like the day after independence will be similar to the day before …”) But by putting social justice at the centre of its campaign, the SNP harvested yes votes in Scotland’s poorest districts, and repoliticised large parts of the population that had been alienated by a sclerotic and self-serving Labour party.

The trouble is that to redistribute wealth, a state needs to have it. North Sea oil that in the summer of 2014 sold for $115 a barrel now sells for $47, and in the months between has sold for much less. Scotland’s share of oil tax revenues collapsed from £1.8bn in 2014 to £60m in 2015. In that year, Scotland’s fiscal deficit rose to nearly £15bn – that’s equivalent to 9.5% of Scotland’s GDP, or more than twice the proportion for the UK as whole. Utilitarian nationalism had prospered on the promise that there would be more money (or at least, not less money) for everyone, as well as well-funded social provision. For the foreseeable future, that looks impossible.

A show of support for the remain campaign in Edinburgh. ‘Brexit has probably made independence more attractive than ever, even to those like me who no longer live in Scotland.’ Photograph: Clodagh Kilcoyne/Reuters

An important moment of revisionism came last Sunday, when in an article published to mark the second anniversary of the independence referendum Sturgeon wrote that the case for full self-government “ultimately transcends the issues of Brexit, of oil, of national wealth and balance sheets and of passing political fads and trends”. Perhaps “passing political fads” referred to the existential-v-utilitarian formulation, which can easily be criticised as a false opposition; whatever you do with independence, it needs in the first instance to be won.

Brexit has probably made that prospect more attractive to more people than ever before, even to those like me who no longer live in Scotland and have no voting rights there. So we have a paradox. On the one hand, never has Scottish independence seemed so reasonable and desirable, and not just to the Scottish nationalist. On the other hand, never in the modern era has it seemed less viable; as well as declining oil revenues there is the problem of the hard/soft border with its neighbour and biggest market, England, should Scotland rejoin the EU after the UK leaves.

An older fashioned nationalism may be the consequence: a movement that can call itself a “struggle” and promises no certain material gain; nothing, in fact, other than the hopefully metaphorical sacrifice of blood, sweat and tears. Either that, or the Scottish independence dream collapses with the oil price.