Boris Johnson’s taxation plans may have sailed through the Commons, but that doesn’t mean they’re sitting well with his party. Instead, the prime minister’s push to define a new centre ground has put him at loggerheads with some of his oldest supporters. The politician they had put their faith in to usher in a new era of free market conservatism is treading a path that goes against their values – and what they had envisaged when he entered No 10. Since Johnson used his first week back after the summer recess to break not one but two manifesto pledges – raising national insurance and reneging on the pensions triple lock for a year – a backlash is under way that goes well beyond the House of Commons. Conservative grandees have gone on the attack, with William Hague warning the prime minister that this week will become a defining moment for his premiership and provide a “recruiting cry for fringe parties”. Free-marketer thinktanks have seen red, with the director general of the Institute of Economic Affairs, Mark Littlewood, describing it as “a moral outrage”. Some of the strongest criticism is from the publications that backed Johnson at the election. His former paper, the Telegraph, has said the move is “deeply cynical”, while the Sun has objected to the raising of taxes, questioning what exactly has happened to the one time “champion of the Brexit buccaneers” who vowed to rip up Brussels’ red tape. They are not alone. Ministers complain privately that they didn’t come into politics to raise taxes, while Brexiter MPs wonder what exactly happened to their hopes for a “Singapore-on -Thames”. “We’re putting our faith in the prime minister but no one is certain this is a good idea,” says one Tory MP. Others fret that the decision to break a manifesto pledge will hurt them most in so-called red wall seats. While some Tory MPs take the view that the risk of the NHS backlog becoming a toxic issue is greater than the risk of raising taxes, many of those who backed the plans simply believed that Johnson would do it regardless – so there was little point being on the wrong side. The threat of an imminent reshuffle helped focus minds. “Given there’s another vote next week, the joke doing the rounds is that we’ll be threatened with a reshuffle again in a few days’ time,” says one member of government. So why in the face of all this opposition did Johnson choose to press on? He knows what his internal critics are slowly clocking on to: there is currently no viable alternative to him. Johnson’s position as leader, with a majority of 80, gives him a level of authority that Theresa May and David Cameron could only have dreamed of. It means would-be Tory rebels have their work cut out to have influence. As for critics outside parliament, the judgment across government is that they’re not about to switch sides and endorse Labour. Particularly at a time when Labour is floating a wealth tax and Keir Starmer’s position looks under strain. What’s more, there’s no Nigel Farage putting pressure on the Tories from the right. Before Brexit, Tory rebels had leverage as they could warn No 10 about the possibility of losing votes to Ukip. The EU referendum pledge, after all, came about because of how worried Cameron was about the splits in his party and the ways in which Ukip was eating into the Tory vote. Could this change? Tory strategists take the view that although it is easier said than done, there is in theory the market space for a party on the right that could capitalise on the perceived cost of the government’s green, net zero agenda along with the desire for lower taxes. The worry isn’t that it could compete with the Tories for seats but instead take some points from their base. The Reform UK party is already trying to occupy some of this ground. But for now all critics can do is try to appeal to Johnson’s sense. Given he is a politician who does not like to be boxed in – or tied to one ideology – there is always a chance in people’s minds that he could come out on their side. The prime minister has often shape-shifted when needed – and shown that he has astute political judgment. This is also why the prime minister will probably be aware that, despite seeing off a Tory rebellion, he is not out of the woods yet. The most worrying part of the week for him won’t be in the chamber or in his favourite papers, but the YouGov poll released overnight. Following this week’s announcements, it puts the Conservatives on their lowest level since the 2019 election – with Labour just ahead. For Tory MPs, going against your low tax principles and winning elections is one thing. Going against them and trailing in the polls is quite another. Johnson’s relationship with his party and supporters is ultimately a transactional one. Given he can’t be tied to a particular outlook, his biggest selling point is the idea that he is a winner. Unhappy Tories are willing to put aside some of their grievances for a politician who can show they have public backing. But if both aspects go, Johnson will soon discover that he needs all the friends he can get. Katy Balls is the Spectator’s deputy political editor