From this week I have become a citizen of a nuclear-free nation. While England and Wales set course for a new generation of nuclear power stations to safeguard electricity supplies and reduce carbon emissions, those of us in the happy position of living in Scotland can wash our hands of the moral, ethical and ecological objections to nuclear fission, and watch, with polite but detached interest, as our close, but thankfully not too close, neighbours embark on the rancorous and divisive debate over energy supplies.

I do not feel particularly proud of my role in all this. Indeed, I may fall prey to the occasional surge of Presbyterian guilt. But there it is: when Alistair Darling, the Trade and Industry Secretary, announced on Wednesday that the great decision had been taken in principle, and that Britain was to become, once again, a nuclear nation, he spoke for just one part of that nation.

Alex Salmond, Scotland’s First Minister, has confirmed that he remains opposed to nuclear power, and will not approve the building of any new stations on Scottish soil. “There is absolutely no chance of us allowing a new nuclear power station in Scotland,” he told the BBC.

He has, of course, no control over energy policy, which is a matter reserved to Westminster, but his executive certainly has the right to block any planning applications to begin replacing the two nuclear power stations, at Torness and Hunterston B, which account for a third of Scotland’s electricity supplies, and which reach the end of their productive lives in 23 and 11 years respectively. If challenged, he will point to a small, but telling clause in the 1989 Electricity Act, which long predates devolution, and specifies that the consent of Scottish ministers is required for “the construction, operation and extension of power stations with an installed capacity in excess of 50 Megawatts”.

The fallout from the SNP’s policy has hardly been felt yet. But the power companies have already accepted the reality of a Scottish veto. British Energy acknowledges that Scotland is now the least attractive part of the UK for any new generation of nuclear power stations, and will concentrate instead on sites in England and Wales. “There are economic and political decisions that make Scotland – at this moment in time – a less attractive option than the South of England,” said a spokesman diplomatically.

To which the response from us truculent Scots is likely to be: “I’m all right, Jock.” Riding high on support from a broad consensus of Green, Liberal and popular opinion, which is still largely anti-nuclear, we can explore the comforting options of alternative energy, secure in the knowledge that, in a couple of decades, when the last of our nuclear stations closes down, the oil is running out, wind power is less reliable than we had hoped, carbon emissions are still rising and other sources of energy have failed to fill the gap, we can always fall back on energy supplies from England. These, of course, would include nuclear power. At the moment Scotland produces more energy than it needs, thanks to its own nuclear and hydro supplies. These are exported south via an expensive and not always cost-effective interconnector. But if the worst came to the worst, the flow could always be reversed so that Scottish lights continue to blaze.

I have the sneaking feeling that the English might not be entirely happy about that. In fact, I cannot imagine anything more likely to inflame anti-Scottish opinion than the realisation that the political disruption, security risks and potential health hazards that will accompany any expansion of Britain’s nuclear ambitions will be borne entirely by England and Wales, while Scotland, happily detached from the furore, stands ready nevertheless to benefit from the power they produce.

It is an untenable position – morally bankrupt as well as politically damaging. By clinging to a vote-winning pledge and backing away from even a period of consultation over the nuclear option, the SNP has demonstrated that it has not yet made the transition from party of protest to responsible government. Saving the planet is more important than winning elections, and every scientist who has examined the facts objectively accepts that nuclear power must be part of the world’s energy balance.

James Lovelock, our premier and most passionate eco-scientist, compares the Earth to a patient with type 2 diabetes, for whom there is only one cure: “Nuclear energy,” he says, “is the medicine that sustains a steady secure source of electricity to keep the lights of civilisation burning until clean and everlasting fusion, the energy that empowers the Sun, and renewable energy are available.” The SNP’s position could just be sustainable if it had a well-worked-out policy showing how alternative supplies will come on stream in time to close the energy gap. But, as Mr Salmond’s airy statement in Parliament this week made clear, he has no idea how soon, or how reliably, the alternative sources will come good. Most experts agree that none of these sources – wave, tidal, clean coal or biomass – will be available in sufficient supplies to meet the country’s energy needs by 2020. What an irony that an SNP government, were it to be in power then, would have to turn, either to nuclear power from England, or to the supplies of fossil fuels from Russia, which, as Tony Blair pointed out on these pages this week, were unreliable and politically unsafe.

In any event, is it morally acceptable for one part of what is still a United Kingdom to turn round and announce that it is opting out of the shared responsibility for ensuring that all of its people benefit from every conceivable source of reliable energy, with the aim of reducing carbon emissions and slowing down climate change? If I were Gordon Brown, I would be tempted to stand the SNP’s North Sea oil slogan on its head, shut off the interconnector and announce: “It’s our power.”

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