Behind the carefully constructed impression of unity around Rishi Sunak, some Conservative MPs are starting to betray their unhappiness about his government’s response to a seemingly unsolvable problem. The prime minister may be content to let the home secretary, Suella Braverman, act as a lightning rod – as one source put it – for hostile briefings and intense media scrutiny over her controversial reappointment, but doing so is also drawing attention to her failure to tackle the number of migrants and asylum seekers being smuggled across the Channel. It suits Sunak to let someone whom many regard as being installed in the top job out of political necessity take the rap, but Tory MPs remain rattled while the issue is unresolved. They could feel the breath of a rejuvenated Nigel Farage down their necks come the next general election, while the sound of Braverman’s admission the asylum system is “broken” rings in their ears. It was the same acknowledgment made by Priti Patel in 2020 when she was home secretary, and the obvious lack of progress since has alarmed some senior Tories. Sunak was unable to give a straight answer to Keir Starmer’s question in the House of Commons on Wednesday about who had broken the asylum system, and the few seconds of floundering as he reached for a response did little to appease concerns on his own side. Nor did the acceptance that all of Sunak’s summer leadership campaign pledges were under review – likely to mean key policies on immigration could be abandoned. Although there were roars in the chamber for Sunak, MPs spilled out a little more disheartened than they had appeared on the TV cameras. Sunak performed a round among MPs in the tea room soon afterwards and was challenged by several about the failure to stem the flow of people being smuggled into the UK. Such a move is usually reserved for moments when a prime minister is on the ropes. And while his premiership is not in any real immediate jeopardy, it is a sign of how concerned figures in Downing Street are about small cracks in the edifice of unity extending, suddenly and uncontrollably. Privately, some Tory MPs praised Starmer’s performance, saying it was “highly effective” and had left their own party exposed. They said ministers had sought to avoid a protracted battle in parliament over the Rwanda plan to remove those asylum seekers who arrive by irregular means, but had still fallen foul of the courts. Instead, the MPs suggested Sunak should “be prepared to fight a proper political battle on this” and take legislation through parliament to bolster the case for it. With plenty in the party uncomfortable at the idea, it would probably prove to be another political headache, even if Sunak won, and so he is stuck. “The party is disunited on so many different issues,” a government source said. One backbench rebel ready to hold the government’s feet to the fire said: “I’m sure I’m on a spreadsheet in No 10 with ‘dickhead’ written next to my name.” Sunak’s critics have little to rally around yet, at least until the autumn statement. And public potshots on the asylum failure have been limited. The only friendly fire on Wednesday came from the backbencher Scott Benton, who challenged Sunak to stem the number of arrivals and asked: “When can we expect the firm action that the British people are demanding?” Even Penny Mordaunt, who hoped to challenge Sunak for the leadership and turn his coronation into a contest, held a “thank you” drinks for supporters but has still said she will be raising a glass to the new prime minister. But no matter the public displays of unity from Tory colleagues, the true test of contentedness will come on election day. Some MPs say stemming the number of people arriving in small boats is a major issue in their constituencies, and Sunak’s vociferous defence of Braverman only demonstrates a failure to properly grasp the problem. Others say the heightened rhetoric from the home secretary about an “invasion” will alienate compassionate constituents, thereby dissatisfying what is summed up in rather crude electoral terms as the “blue wall” and the “red wall”. Boris Johnson was said to have promised supporters at his own “thank you” drinks earlier this week to join them on the campaign trail for local elections in the spring, and, when the time comes, to help fight to retain the Conservatives’ 80-seat majority at a general election. But six years after Brexit and Vote Leave’s pledge to “take back control of our borders”, and three years after the Tory 2019 manifesto’s promise to “fix our immigration system”, if voters feel those promises ring hollow, Sunak could collide headlong with electoral reality.