Faced with questions from MPs, Boris Johnson was like a blundering schoolboy

Boris Johnson signed off this afternoon by telling the Commons liaison committee how much he had enjoyed his first meeting with them. If that’s true, then either I’m a Dutchman or Johnson has a weird way of having fun. No wonder he has managed to go almost a year before attending Westminster’s most prestigious committee. He came determined to say nothing new about Dominic Cummings and more or less managed it, though it came at a cost. On the wider issues of his government’s response to the pandemic, he mostly flannelled. Some of the questioners, notably Greg Clark, Stephen Timms, Robert Halfon and Darren Jones, beat him all ends up. Yvette Cooper delivered some icy remarks that should send shivers down his spine. Leadership Winston Churchill style it most definitely was not. Billy Bunter in the headmaster’s study kept coming to mind.

Johnson said he had spent a lot of time preparing for the meeting. It felt like a wasted effort. To expect the grasp of detail normally expected of a modern leader was and is hopeless. Issue after issue had to be parked, with promises of written replies later. Because he knew he had to be on his best behaviour in front of the assembled select committee chairs, there was less recourse to the irrelevant analogies and verbal folderols that Johnson often hides behind. The contrast with Tony Blair, Gordon Brown, David Cameron and Theresa May – all of whom were consistently across the detail and submitted more often to attending the committee – was a painful one.

At a time like this, amid a life-changing pandemic and with his government rocked on its heels by its handling of the Cummings affair, there seems only a limited amount to be gained by rehearsing all Johnson’s problems and failings yet again. His standing, which was on the slide before the Cummings story broke – and which has been made spectacularly weaker as a result of it – has not changed. The pandemic is not over: another 412 deaths were announced just before the committee met. The questions that matter, the questions that matter politically, are whether and in what way the liaison committee session is important or has changed anything.

Johnson will think that the session went well. He will think he had the better of the day. He made no concessions on Cummings, whom he managed barely to mention by name. He consistently treated the scandal as the past, going through the motions of saying he understood why it mattered to others but displaying no sign whatever that he understood why. His mantra was to move on, to start talking about the next phases of easing the lockdown, to promise a working tracking and tracing system and lots more shopping opportunities. There will be much more of this in the coming days, not least (though not solely) because it creates new stories and diversions.

It may indeed have worked today. But it is hard to be sure. Johnson and Cummings are not out of the wood yet, whatever the No 10 spin machine would like you to think. The polling is terrible. Johnson and Cummings may damn the press as often as they like, but the story about Cummings was true, not false. The “cut-through” effect of the Cummings story is beyond anything that many people have seen in politics for a generation. It has been particularly damaging in Scotland, as the resignation of Douglas Ross underscored. And there was an interesting reminder, while the committee was in session, of how differently this is seen outside the bunker, when Giles Watling became the latest Conservative MP to call for Cummings’ departure.

No 10 will say he was the first of the day, and so he hardly matters. But Watling’s turn against Cummings is important for two reasons. First, because he based it squarely on what Johnson said - and didn’t say - to the liaison committee. So it is a reminder that the prime minister is continuing to lose allies for new reasons. And, second, because Watling is the MP for Clacton, one of the signature Brexiter seats – the old Douglas Carswell seat, its electorate mostly white, working class and disproportionately old. Clacton is a “blue wall” place. Watling’s defection tells Johnson that one of key things about the Cummings affair is that it risks losing some of Brexit’s most loyal battalions on the one rule for us, another rule for the toffs principle.

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The huge danger for Johnson remains the same as before. It is that he has been found out as someone who a lot of his supporters thought he wasn’t. The point about the Cummings affair is that Watling’s voters in Clacton can see what most people in Britain can also see. Cummings fled to Durham when he did not need to and when the rest of the country was obeying the lockdown. His claim that he exercised a subjective discretion that was authorised in the regulations and the guidance is bogus. There was no such discretion; the rules said stay at home and applied to him. Nor did Cummings do what any responsible person in his position should also have done - take advice. The drive to Barnard Castle story is already a national joke. The BrewDog company has already launched a new Barnard Castle Eye Test beer, the proceeds going to the NHS. I’ve got a case of a dozen on the way.

In the bigger picture, this feels like a turning point for Johnson’s premiership, and perhaps for his government more widely. He would like to rewind the clock. He would like to find himself again at the helm of a government backed by the Mail and the Telegraph, delivering Brexit and promising what are still pretty nebulous new investments in deprived parts of England, while facing a useless Labour leader across the dispatch box. That’s his comfort zone. But there can be no returning to the past, no unlearning the lessons of the past two months. The country has seen a different Boris Johnson now and there’s no going back for anyone.

• Martin Kettle is a Guardian columnist