At the start of prime minister’s questions, Theresa May boldly declared that MPs could do themselves and her a favour by giving up membership of the EU for Lent. Just try to forget that Michel Barnier might rise from the dead on Easter Sunday. No wonder the rest of Europe is under the impression the UK has yet to get the hang of the Brexit negotiations.

Brexit has long since sucked the life out of this government. Though everything has gone wrong, there is still more that can yet go wrong. So we are living in zombie times where ministers are chosen for either their inability or unwillingness to get anything done. Far better to do nothing than risk doing something that will almost certainly turn to ashes. Under the circumstances, inactivity and natural decay are prized virtues.

This lack of energy has now filtered down to MPs of all parties. The only visible signs of life in the chamber are a few, eager backbenchers fighting over a single defibrillator to prevent themselves from flatlining. Most are just content to close their eyes and munch their way through bottles of valium as if they were packets of wine gums. They have embraced their impotence, their fury sublimated into fatalism. Oblivion has become the only sane response to the Brexit car crash. And to the prime minister who is asleep at the wheel.

At prime minister’s questions, May’s synapses were firing sufficiently to get her to her feet. But not much more. Some time over the past 24 hours it has dawned on her that trying to claim that rising levels of knife crime and falling police numbers were entirely unrelated – hell, why not get rid of knife crime entirely by having no police at all? – was not a great argument. Not least when almost every senior police chief is saying the exact opposite. So she tried to head off any awkward questions by saying knife crime had many complex root causes and that it had to be stopped.

The Labour leader started well enough by pointing to divisions in cabinet. Sajid Javid was openly campaigning for extra police resources, while Gavin Williamson had promised to call in the army. Once it had defeated China in the Pacific and paint-balled Spanish trawlers, the defence secretary was certain that a couple of tank battalions would be just the job to put an end to gang culture. His nickname of Private Pike is getting ever more unkind. Dad’s Army’s Pike was never quite that stupid.

Then Jeremy Corbyn suffered a lapse of memory himself. The brain-eating virus doing the rounds of Westminster must be highly contagious. If only he could have remembered who had been the home secretary between 2010 and 2016 when police numbers had been cut by 21,000, then he might have been able to blame her personally. But try as he might, he just couldn’t put a name to a face – even though the face was staring at him across the dispatch box – and the moment passed. His chance to really embarrass the prime minister had been missed.

May couldn’t believe her luck and instantly defaulted to Maybot mode. Her ability to miss the national mood is uncanny. Knife crime was absolutely nothing to do with her. It was all Labour’s fault. The teenagers who were knifing each other now were doing so out of some long-repressed rage at Tony Blair. Corbyn nodded involuntarily. He could understand that feeling.

Then he got a grip and pushed the blame back on to the Tories’ austerity policies. Here things took a turn for the surreal as May now tried to claim that austerity had only ever been a mirage and that it was Labour policies that would create austerity. So now the reason teenagers were knifing each other was because they all had it too easy. Well-paid jobs and plenty of leisure time had created an uber-class of people who could only relieve their affluence-induced boredom by killing one another.

It was an easy enough win for Corbyn. But not nearly as convincing as it should have been. Labour should have May on the ropes over her party’s laissez-faire approach to knife crime. There should be outrage that so many young people are getting killed. Instead, there was silence. Both leaders are only capable of inducing apathy among their backbenchers. It’s hard to rustle up respect from others when you don’t even respect yourself. Teenagers are dying on the street. May and Corbyn are dying on their feet. And taking the country down with them.