After all the turmoil of recent years, you might think British politics had lost its capacity to shock. But a week in which some of the angriest voices raised against this week’s shameful climbdown on net zero come not just from passionate greens, but from car manufacturers and the energy industry? Now we really are through the looking-glass. What happened this week was the most surreal opening to a long election campaign – for that’s surely what it was – I can recall. For the leader of the erstwhile party of business to water down climate policy and still somehow contrive to end up getting furiously attacked for it by Big Auto is surprising enough. Managing simultaneously to leave Boris Johnson claiming the moral high ground and Liz Truss looking relevant, given she had just called for such a retreat, is something else. The next step in a promised string of bold decisions may be to kill off various bits of the HS2 rail project, judging by Rishi Sunak’s public refusal to rule that out this week. Levelling up? Forget it. There could be few better metaphors for this era in politics than a fast link between central London and the north that may end up costing billions without actually ever reaching the north, and possibly not central London either (the Birmingham to Manchester stretch and the bit linking Ealing to Euston are reportedly under review). Though the death of the levelling up dream may be less emotive than the junking of plans to save the planet, both U-turns represent the torching of what credibility the Conservatives had among the people most likely to give the party the benefit of the doubt, and both have much deeper consequences for where the country is heading. Once again, Britain is starting to look in the eyes of the world like an unreliable ally, prone to making and then breaking promises on the wheel of its own political incompetence. Rumours of a net zero retreat first started circulating last weekend, yet carmakers meeting the transport secretary, Mark Harper, on Monday afternoon reportedly left under the impression that the 2030 ban on new petrol and diesel car sales was staying. Ford, which said it had ploughed £430m into electric car production in Britain with more to come, issued an unusually angry public rebuke stressing the need for “ambition, commitment and consistency” in No 10; BMW, which had only just announced plans to make electric Minis at its Oxford plant, stressed that “we and the whole automotive industry [need] clarity”. Renewable energy firms were equally blindsided by the news breaking hours after a meeting where ministers reassured business leaders that net zero was a top priority, according to Energy UK’s Emma Pinchbeck. “It’s just chaos, isn’t it?” said an angry Juergen Maier, a former CEO of the renewable energy giant Siemens and vice-chair of the Northern Powerhouse Partnership. “Everybody is now sitting and wobbling and wondering. And I tell you what, they won’t be investing in the UK.” The general air of chaos surrounding the announcement may seem trivial compared with the substance of it, but both have a direct impact on the future of the planet: as Pinchbeck pointed out, up to 70% of the cost of reaching net zero is supposed to be stumped up by a private sector that now doesn’t know what to believe, and won’t risk pumping billions into products for which the market may suddenly disappear. Outrageous as the climate climbdown itself is, there are at least some grounds for hoping it’s less apocalyptic than it sounds. When a prime minister starts padding out his big U-turn by scrapping policies that never existed in the first place – from an imaginary tax on meat to some weird fever dream about seven rubbish bins – it’s worth questioning exactly how deep it goes. Delaying the ban on selling new petrol and diesel cars until 2035 is a blow but could at least be a short-lived one, with Labour promising to move it back to 2030 if it wins next year’s election. The scrapping of an obligation on landlords to fit insulation and other energy-efficiency measures is seriously bad news not just for the climate but for renters left to shiver in cold, damp housing; delaying the cutoff date after which homeowners won’t be able to get a new gas boiler will also have an impact. But new, more generous grants for homeowners buying heat pumps look like an attempt to speed up their adoption by other means. What’s worrying, however, is the cavalier way in which all this has been presented by a government scrabbling for survival. Ministers are behaving as if they think business will grumble a bit but rally round in the end, for fear of a Labour government. But global companies in 2023 don’t think like that. They can deal with either Sunak or Keir Starmer, but the one thing they expect is a clear line around which to plan. Given how long new cars take to design and build, the automotive industry thinks a decade ahead when planning production sites. They don’t take kindly in Michigan or Japan to hearing that everything’s changed at the last minute because of canvass returns from somewhere called Mid Bedfordshire. The truth is that Britain had already become a less attractive place in which to make things, having left the EU single market. But by moving faster towards net zero than other countries, it was at least promising to create a pool of early adopters who would be nudged into buying electric cars faster than German or Spanish or Californian drivers. When Sunak says soothingly that this U-turn just brings us into step with other countries, what he neglects to mention is that being out of step was meant to be our big post-Brexit trump card. All this might be less corrosive if it didn’t reinforce a fear of British unreliability dating back to the 2016 referendum, when big multinationals were privately assured by David Cameron’s government that remain would win comfortably, only to be blindsided by a vote to leave. Since then they’ve had to deal with the endless uncertainty of Brexit negotiations, the one-man chaos engine that was Boris Johnson and the economic hallucinations of the Truss era. The whole point of Rishi Sunak was that he was meant to be different, a man the world could do business with. Yet now to placate the Tory right, he is suddenly and not entirely convincingly being repackaged into something that looks wearily familiar. This is scorched-earth Conservatism, in an alarmingly literal sense. It cannot be allowed to burn the country down with it. Gaby Hinsliff is a Guardian columnist