Rishi Sunak’s retreat from the government’s net zero pledges triggers large- and small-scale conclusions alike. These range from a message about the future of the planet’s place in the prime minister’s priorities, at one extreme, to the anxiety it betrays about how to manage his way through his first party conference as Conservative leader, next month, at the other. Nevertheless, Sunak’s move should be seen as a short-term electoral gamble rather than a massacre of the entire net zero agenda. That does not mean that it isn’t damaging to the net zero credibility established imperfectly by previous Tory prime ministers, let alone to Britain’s longer-term reputation on climate action. It is all these things. If it is electorally successful, the shift could also become more fundamental and more lasting. But Sunak’s calculation, which will undoubtedly have been extensively poll- and focus group-tested by his advisers, is that public opinion is currently more concerned with the here and now than it is with 2030 or 2050. Although the various retreats – on electric cars, boilers, insulation and diet, among others – are being depicted as “pragmatic”, the package embodies political rather than policy pragmatism. The timing of the shift confirms that navigating the Manchester party conference, starting on 1 October, is a genuine concern. The retreat is designed to shore up Sunak’s conference credibility with the party base that elected Liz Truss, rather than him, just a year ago. This takes on special heft in a week when Truss explicitly opposed the net zero commitments. But the pullback points beyond Manchester, too, to the pivotal importance of two rather unglamorous spots on the English electoral map. Parliamentary byelections in Mid Bedfordshire and Tamworth are due in four weeks’ time, on 19 October. Both had huge Tory majorities in the last general election: more than 24,000 in Mid Beds, more than 19,000 in Tamworth. Both, though, are now serious opposition targets. Sunak’s green retreat should be seen as an 11th-hour punt to save these two seats for the Tories. The case for a throw of the dice before the byelections is seductive. The Tories are generally tired out, washed up and fatalistic. They have lost a succession of earlier byelections in seats that had once seemed as safe as Mid Beds and Tamworth. They remain well adrift of Labour in the national polls. And the two former MPs in the byelection seats, Nadine Dorries and Chris Pincher, both quit amid controversy. The Tories need to attract attention with something new. There are no prizes for guessing what. The one shaft of electoral sunlight this year for the Tories was the victory in the Uxbridge and South Ruislip byelection. That win owed everything to a campaign focused on London’s tax on high-emission vehicles. The result did more than save one Tory seat. It energised the Tory right’s rumbling long-term opposition to the government’s net zero targets. At this point, it is worth remembering why Sunak is the Tory party leader at all. It’s not because he won an election. He didn’t. It’s not because he has a radical policy agenda. He hasn’t. Nor because he is a brilliant leader. Nor because he is hugely popular in the party. It is simply because, following the ruptures and implosions of the Johnson and Truss governments, Sunak was seen, rightly, as the Tories’ least bad option for damage limitation. He’s the guy who might just manage to land the stricken Tory plane on the water’s surface, rather than nosedive it into the depths. Sunak’s retreat is designed, more than anything else, to do an Uxbridge in Mid Beds and in Tamworth. Even in the byelection context, however, this is still what American football coaches call a Hail Mary: a last-minute hurl of the ball by a trailing team that just might snatch victory from the jaws of defeat. It is a big risk. If the Tory party’s net zero supporters get their act together, they could hurt Sunak’s reputation a lot, not least with young voters. And if Labour sweeps home in Mid Beds and in Tamworth, he will be damaged even more. But suppose instead that Sunak wins the byelections, what then? That’s the gamble he has now taken. Expect the green retreat to be front and centre of everything the party brings to those two campaigns. If the Conservatives hold on, especially if they hold on in both contests, Sunak’s achievement will be seen by his party as the most brilliant retreat overseen by a Tory prime minister since Churchill at Dunkirk. He will be the hero of the hour. The retreat will also instantly become the template for British electoral politics in 2024. The Conservatives will undoubtedly conclude that they have a sniff of ousting Labour’s Sadiq Khan in the London mayoral contest next year. They may even be right, in spite of the lacklustre Tory candidate, Susan Hall. Tory hopes would certainly increase if Jeremy Corbyn is tempted to run as an independent, splitting the Labour vote. But the main lesson would be for the general election. If Sunak succeeds in selling his green retreat both to his party and to Tory voters and then starts to win more elections in the aftermath, then he is not going to stop there. The repositioning would be likely to continue, shifting the British Tories increasingly decisively away from the environmentally consensual party of the David Cameron era into a more sceptical party like the Australian Liberals. There would be no shortage of voices on the right urging him on. Earlier this month, the pollster and academic Matthew Goodwin argued that only 7% of 2019 Conservative voters want their party to prioritise net zero if it increases their bills, against 72% who want to prioritise cost of living reductions. Goodwin dubs this “the next big populist revolt”. Plenty of backbenchers agree. So do some cabinet ministers. Sunak is not a strong enough leader to resist or control this. Earlier this month the government apparently promised the BMW car manufacturer that its electric car plant investment at Cowley, Oxford, would not be subverted by any retreat from the 2030 phasing-out of petrol-driven vehicles. Only a few days later, Sunak is doing precisely that. We are a long way from Sunak as the safe pair of hands or as the leader who understands business. Indeed, when Boris Johnson once said “Fuck business”, it now seems he spoke for Sunak, too. Martin Kettle is a Guardian columnist