You learn a lot about a person at a time like this. Not so much about the prime minister, who has resigned. Keir Starmer has already revealed how he deals with a personal loss. But about the leader of the opposition. Here was a chance for Kemi Badenoch to show her human side. To give the world a rare sighting of her empathy gene. But Kemi just can’t go there. She can’t read a room. She has only one mode. All-out attack.

Other people’s moments of weakness are just material for her to use against them. Even now, she probably thinks she played a blinder at prime minister’s questions. A chance taken to humiliate Keir when he’s down. She has no idea how graceless she is. How charmless.

All the more so because she has played no part in Starmer’s resignation. The Conservatives have just been bystanders. There has been no dramatic intervention by Kemi. No set piece in which she has exposed his weakness and forced the issue. Keir’s departure was purely between him and the Labour party. It was Keir’s MPs who had given up on him. No one else.

One day she will find this comes back to bite her. Those whom she has ripped apart on her way up won’t hesitate to do the same to her when she is on the way down. Which may be sooner than she imagines. She certainly has no idea of how to make friends with people.

The mad thing is that it would have taken so little for Kemi to have come out of PMQs looking good. In their first exchanges after a Downing Street resignation, it’s customary for the leader of the opposition to say something complimentary about the outgoing prime minister.

It doesn’t even have to be very much. She could have said she admired his steadfast support for Ukraine. Or gone for the human touch. That she had enjoyed the conversations they had held in private. Had loved meeting his wife and kids. Wished him all the very best. But Kemi would rather die than do this. She sees kindness as a sign of weakness. Would have cost her what passes for her self-worth.

Had she done this – allowed even a forced croak of kindness to escape her lips – then everything that followed would have been OK. Kemi would have bossed the show. As it was, she crashed and burned. Her language becoming progressively more angry and violent the longer she went on. It was the behaviour of a spoiled child. A playground bully whom her party doesn’t dare to call out.

There again, these occasions are always slightly surreal. A living tableau of power seeping away. Passing from one leader to the next. The same Labour MPs who had cheered Andy Burnham as he was sworn in on Monday and had queued for a selfie in Westminster Hall were now cheering Keir as he arrived in the Commons. Make your minds up, guys. Or maybe it’s all just ritual anyway. Some kind of performative Pavlovian dance.

Walking in with Starmer was Rachel Reeves. The chancellor had been conspicuous by her absence on Monday. Nowhere to be seen in the Downing Street lineup of cabinet ministers as Keir announced his resignation. Hell, she had only had to step outside her front door. Even the increasingly insufferable Darren Jones had waved Starmer off before announcing he had checked on Burnham’s economic credentials and pronounced himself satisfied. The stock markets were safe with Andy, he said. Phew. That will be a big relief to us all to know that Dazza has given the thumbs up. The job queues outside Andy’s front door were getting longer by the minute.

If Reeves had looked morose as she arrived at the Commons, she was soon looking utterly abject. For, having begun by needling Starmer about the arrival of the king of the north, Kemi then turned her fire on Reeves. She had been useless when she had started the job and she was useless now. And now she was doing her best to distance herself from her old boss. Rachel appeared close to tears. She will go down with this ship.

That was Kemi just getting started, though. Next in line was the energy secretary. Ed Miliband. A serial betrayer, she insisted. First he had done for his brother, now he was doing for Keir. Typical of Kemi to pick on the man doing the most to stop the climate crisis on one of the hottest days of the year. Yet another example of her inability to think on her feet. Or even when sitting down.

Bridget Phillipson was dismissed as a “spiteful class warrior”. Starting a row between the two that continued long after the session had ended. When Kemi said Starmer had 400 knives sticking in his back, the speaker tried to intervene by asking for MPs to moderate their language. Two MPs have been stabbed to death in the last 10 years. But Kemi wasn’t giving an inch. She doesn’t know how. No one has ever heard her say the word sorry.

Meanwhile, Keir was almost in his element. Many previous prime ministers have felt oddly liberated in the weeks between the announcement of their resignation and their actual departure. As though the pressure was finally off and he was free to be himself. He made fun of the Tory result in Makerfield, defended Reeves, Miliband and Phillipson, before signing off with the observation that, unlike all Tory prime ministers, he was leaving the country in a better place than he found it.

It was left to others to point out to Kemi the unpleasantness of her approach. Ed Davey directed his opening remarks directly to her. This had been a moment to acknowledge that politics has a personal cost. And she had typically failed to rise to the moment.

The Tory MP Desmond Swayne was pure class in quoting a Hilaire Belloc poem. A handshake across the divide of the Commons. Starmer replied with a story of how Swayne had turned up at his rental in the New Forest with a bottle of champagne. A gesture that was lost on Kemi. Why would he waste £30 on a present for the prime minister? She wouldn’t spend that on her own kids. Swayne was just some kind of loser. A softie at heart who had gone to the bad. She regretted nothing. She would apologise for nothing. Never say a kind word when a cruel one will do.