IT WAS a long time ago – about the time that the First Minister would have been starting primary school – that the SNP adopted the stirring slogan: It’s Scotland’s Oil! A lot of water has swirled around and lots of barrels of oil flowed from the North Sea since then, but Nicola Sturgeon was still employing a variant on the theme four decades after the election campaigns of 1974.

In 2014, when there was some campaign or other that the SNP was eager to push, Ms Sturgeon insisted that a “bonanza” was in the offing, and that Scotland was on the cusp of a “second oil boom”.

Alex Salmond, whom readers with long memories will recall had some association with the SNP, argued that oil revenues would comfortably cover an independent Scotland’s budget deficit for decades to come, though he based his sums on an estimate in oil prices about $100 a barrel more than they turned out to be a couple of years later.

Had we voted Yes in 2014, that would have had the inconvenient effect of leaving a hole of $30 billion or so in the new nation’s finances, compared with Mr Salmond’s cheery projections.

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Never mind. Perhaps it’s for that reason that we haven’t heard quite so much nationalist enthusiasm about oil and gas revenues, or – as we frequently did until quite recently – about the opportunities to be seized by setting up our own version of the Norwegian fund that’s added some $1.3 trillion to their coffers over the years. It may explain why, while not actually opposing the development of the Cambo oil field, the First Minister has written to the Prime Minister, asking him to “reassess”.

Or perhaps it’s something else, such as the shift by almost every government in the developed world to arguing for greener energy sources. Plenty of environmentalists maintain that this is a very belated conversion; a lot of them argue that even the targets that have finally been adopted (and the UK’s are about the most ambitious, and some would argue, therefore the least realistic) are not enough.

Whether the doom-laden predictions of the likes of Extinction Rebellion are overblown, or the aim of Boris Johnson’s green agenda to reach net zero by getting shot of traditional cars and domestic boilers within a decade are a ludicrous and unaffordable pipe dream, however, there is no particular reason to doubt that, in the very recent past, there has been an apparently sincere shift in policy.

That applies – and judging by much of their rhetoric, in spades – to the SNP, too. The fact that the party is and has been in a de facto coalition with the Scottish Greens no doubt plays a part in that position, but even so the conversion to the Green cause is almost certainly genuine. By 2020, 97 per cent of Scotland’s electricity demand was being met by renewables, such as wind and hydropower (though transport, heating and agriculture are still reliant on fossil fuels).

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The Government is well aware of Scotland’s considerable natural advantages in this field which, happily for them, also turns out to be politically convenient, given that environmental causes are now seen by almost everyone under the age of 60 as at least progressive, and by many as urgent and essential.

Both Ms Sturgeon and Mr Johnson are, I’m certain, sincere in wanting a greener agenda, though that’s not to say that their plans will correspond with the most useful action. But then nor, often, do those of the wider, capitalised, Green movement, which often opposes, for example, nuclear fuel and GM crops, about the most effective tools in the fight against carbon emissions and the strains of population growth respectively.

The parties that have moved environmental concerns up their lists of priorities, but for whom it is not, as it were, their raison d’etre have to consider wider economic and social implications. In Scotland’s case, that includes details such as the 10 per cent of the country’s GDP that still comes from oil, gas and associated industries, and the declining income from hydrocarbon taxes.

In this respect, Ms Sturgeon shows signs of being slightly more in touch with inconvenient realities than the Prime Minister, with his airy, uncosted announcements of a total ban on conventional cars and replacing everyone’s boiler (at about £18,000 a go). The desire of both to be seen to push ahead with greener policies is, as I say, probably rooted in genuine conviction, and may be bolstered by an eye to popular opinion, but the thing that I’d be prepared to bet is the proximate item in their thinking is the upcoming Cop26 summit in Glasgow, and the swanking about the world stage prospects that it offers both of them.

That may not always make for the best decisions. Mr Johnson was recently complaining that plans to open a new coal mine in West Cumbria were embarrassing him in the run-up to the conference, but you can’t make steel without coal, and at the moment we ship it in from Australia and the US, so it might actually be the more environmentally responsible measure. Similarly, Scotland’s transition to net zero (where our target of 2045 is sooner than the UK’s) is going to be an expensive business, and oil and gas, as the First Minister pointed out in a recent Tweet: “supports thousands of jobs in Scotland”.

This led her, when challenged on her stance on Cambo, to say “Look, I’m not going to stand here...” – a formulation that she often employs when she means “I wish you hadn’t asked me that” – and then follow it with the extraordinary, indeed unprecedented statement: “It’s not a matter for the Scottish Government.”

Until now, nothing – whether it is the power to call a referendum unfortunately outwith Holyrood’s legal competence, or reserved matters such as foreign policy or the UK’s nuclear defence capacity – has ever, in her estimation, not been a matter for the Scottish Government, even if that has been to moan about Westminster.

No one can really blame her for taking this tack. It shows, if anything, that Ms Sturgeon has some appreciation of the real costs of action to improve the environment, and the gap between easy public declarations of Green virtue and hard policy decisions. All the same, it’s quite a turnaround to hear an SNP leader declaring that it’s not Scotland’s oil.

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