Humza Yousaf won’t be the last leader to be forced to the brink by impossible promises

The Scottish National Party is paying the price for unrealistic green targets

I’ll tell you what happens with impossible promises. Neil Kinnock’s words echo down the decades: “You start with far-fetched resolutions,” he said, confronting the Trotskyists who ran Liverpool. “They are then pickled,” he said, and you end, in words that Labour modernisers recite as a creed, “in the grotesque chaos”.

In Militant’s case, the chaos meant a council run in the name of the workers hiring taxis to hand out redundancy notices. In the Scottish National Party’s case, it may mean the premature end of its government in Edinburgh after 17 years.

Humza Yousaf, the first minister, says he will fight on, and the SNP is desperate to avoid an early election. They may succeed for now, but my sources say that Yousaf is “done”, and that the SNP doesn’t have an alternative leader who could hold together a broader coalition than he can. Kate Forbes, the former finance minister, who lost to Yousaf in the leadership election last year, might be a more capable politician, but her social conservatism means she is even less likely to be able to keep the Greens on board with a minority SNP government.

This is what happens with impossible promises. This one was put in the pickle jar by Nicola Sturgeon, the former first minister, five years ago. She wasn’t in a formal coalition with the Greens then, but she needed their votes in the Scottish parliament, because the SNP on its own was two seats short of a majority.

It was the year that Theresa May left her “legacy by target” of legislating for a net zero contribution to global warming from the UK by 2050. Sturgeon’s reflex was to outdo London, so she set the target for Scotland five years earlier, by 2045. But she also wanted to set an intermediate target for 2030, which also seemed like quite a long way off at the time.

She was going to aim for a 70 per cent cut in greenhouse gases by 2030, from a 1990 baseline, but the Scottish Greens wanted 80 per cent, and Labour and the Liberal Democrats called for 75 per cent.

She went for 75 per cent. This was the target that led to the current crisis. It was noted for its ambition at the time. Praised by some; regarded quizzically by others who commented on a dramatic change of heart by a party that had built its mythology on the grievance of “Scotland’s oil”. Indeed, Sturgeon had fought the previous Scottish election on the promise of a “bright future” for the North Sea oil industry.

Now time and reality has caught up with that unrealistic promise, made by a devolved government that doesn’t even have responsibility for energy policy. It was undone by Chris Stark, the outgoing chair of the UK-wide Climate Change Committee – the independent body set up to monitor progress on climate targets. He warned at the time of the climate change summit in Glasgow three years ago that the Scottish government’s target was “overcooked”.

Last month, his committee declared it dead: “The acceleration required in emissions reduction to meet the 2030 target is now beyond what is credible.” The SNP-Green coalition government accepted the verdict on 18 April. Màiri McAllan, the SNP minister for net zero, tried to blame Rishi Sunak’s “backtracking” – on UK targets for electric vehicles and heat pumps – for the target being “out of reach”.

The Greens prepared to quit the coalition, but Yousaf thought it would be a good idea to sack the Green ministers in his government before they could resign, commenting afterwards, “I didn’t intend to make them as angry as they are.”

He should have let them resign and then asked them why. Were they objecting to the target being too weak in the first place? Were they resigning in protest at the failure to meet it, by the government of which they were part? Or were they just howling at the unfairness of the universe and the unstoppable rush of time?

The failure of the SNP-Green coalition holds wider lessons for politics, and especially the politics of the likely Labour government of the UK. Keir Starmer and Rachel Reeves have ditched one impossible promise – or, rather, one undesirable one – of borrowing £28bn a year, but they have retained another. They still pretend that a Labour government will decarbonise all UK electricity by 2030 – coincidentally the same date that tripped up the SNP.

I don’t think this pledge will trip up a Labour government in the same way. It seems to be regarded as a statement of intent, a way of saying “we are going to try very hard”, rather than a binding commitment; and Starmer will not be in a coalition government with the Greens.

But a Labour government is going to have to face up to a lot of interim deadlines on the way to net zero. It is going to have to learn to love “the whooshing noise they make as they go by”, in Douglas Adams’s words. The SNP can say that all parties supported its target, but what matters is which party is in charge when the connection between reality and the target snaps.

At some point, a British government will have to confront the tension between targets plucked out of empty space many years before the pluckers thought they would be answerable for them, and the willingness of citizens to vote for policies that will make them poorer.

In years to come, Rishi Sunak may be praised for his realism in beginning the difficult business of making targets fit what is possible. But in the meantime, it is likely to be a Labour government that will have to face up to a Humza Yousaf Moment when unrealistic promises catch up with it.

I’ll tell you what happens with impossible promises. They end in the grotesque chaos of discrediting the worthwhile causes they once sought to promote.