I was never a fan of Theresa May. She won the 2016 leadership election by default and because the one argument stronger than “Anyone but May” was “Anyone but Leadsom”.  As an active Conservative, she had always seemed to me to be one of those politicians who flourish by failing at every job they have in a manner that is too dull for anyone to remember, but with a loyalty to the party line of the day that is so unwavering and unimaginative that it is useless. She, it was, who coined the notorious “nasty party” phrase that has hung around good decent Conservatives’ necks like an anchor of unpleasantness ever since. But aside from that, can you remember anything she ever actually did well?

Being rubbish at all previous jobs is, of course, no necessary bar to being a good Prime Minister. I hoped she might prove to be a political Devon Malcolm. Malcolm was a cricketer, a bowler who was dull, ordinary and fairly ineffectual until he came to bowl against the top players on the top wickets, at which point he suddenly became a world-beater. Perhaps May could have been the same, with her previous weaknesses suddenly transformed into strengths?

Alas, no. From the start she lacked any of the necessary instincts for the task. She got that she had to implement Brexit (how could she not?), but for how to do that best and keep party and country together she had none of the required intuition. She got off on completely the wrong foot, insulting our friends and allies with talk of lists of foreign workers and a focus on immigration. She become enslaved by her officials, believing wrong advice (both legally and, more fundamentally in this instance, politically) on commencing trade negotiations with non-EU countries.

Having backed Remain in the EU referendum campaign she had no Brexit principle of her own, no red line she personally wanted to stand upon with a “Back me or sack me”. With her Home Office background, and having elected to opt in to numerous EU security measures even when the UK had negotiated opt-outs, she just never saw why coming out of programmes like the European Arrest Warrant were important, and on issues like the Irish border she comes at it with a security hat on. Not “How can have the border as soft as is feasible given that we’re becoming a sovereign country again?” but, rather, “What trading relations should we agree with the EU that leaves the Irish border security situation no worse than at present?”

Almost uniquely, I don’t think it was a mistake for her to have called a General Election. I think it was absolutely necessary to have a General Election so that that vast majority of MPs that had backed Remain could face their electors and promise to implement the referendum result, restoring legitimacy to the system. It was also necessary to have a General Election to buy a little time for transitional arrangements so whatever transition we agreed to was complete by the time of the General Election that followed Brexit. I don’t even blame her that much for the result. The Conservative vote share was as high as any of Thatcher’s landslides. Losing the majority was mainly about Corbyn, not about her.

But since the General Election she has become ever more hapless. The government just about staggered through the Phase 1 Brexit negotiations to a result that would have been okay-ish (if imperfect) if we’d insisted on sticking by it. But she didn’t. I think she didn’t really understand what were the really important gains for the UK from that Phase 1 deal.

Not knowing what to do — not having the right instincts or personal red lines; not knowing when to force the Cabinet to choose and how to tell them to resign if they didn’t like it — and believing ever-more-absurd campfire horror stories about the consequences of no deal, her only tactic has been delay: agree a transition with the EU even though the EU insisted on reneging on the Phase 1 agreement to agree to that transition; put off Cabinet decisions on the future relationship with the EU; make no choice or stand or strategy modification on the Irish border; delay, delay, delay and survive until tomorrow, next week, next month, for something may turn up.

These are not issues that can be resolved by reading the briefings your officials give you really thoroughly and then reading them again and again. Almost everything about Brexit involves risk and instinct and playing it by ear and standing on some core principle, because it is a new situation unlike anything anyone in Britain has encountered before.

But if, like May, you have no relevant core principles and never wanted to do it in the first place, and if, like May, your core instinct is to maintain order and as little change as possible while we get to tomorrow, and if, like May, security is more important than sovereignty and imagination and opportunity, you won’t know what to do and you won’t know why and when it might be worth sacrificing yourself for a larger cause and the flow of history, because that cause is not your cause and that history is not on your side. She doesn’t know, and she isn’t right and she can’t do it.

None of this is news. To be honest, she did better for the first eighteen months than I would have expected of her — a low bar. But she should have been removed last December after the Phase 1 deal, and replaced by someone who believes in Brexit and doesn’t see it as mainly about immigration. The past six months have been hopeless, and she has now deteriorated to the point that many Conservatives view her as even worse than Major — a leader so bad that people like me voted Labour in 1997.

Replacing May will not cure all the ills she has created, and a new leader will have considerable challenges starting from here, both internal party challenges, the challenge of the quasi-Communists on 40 per cent poll ratings on the opposition benches, and the challenge of EU negotiators that have been used to dealing with such weak counterparts that they will take some persuading a new leader might be able to stand for him- or herself at all. But a new leader would be a start.

Conservative MPs must know this. The party needs an election campaign where different candidates offer different visions of what to do next. If the party chooses a leader offering Brexit in Name Only, then fine — we’ll have to see off Corbyn and come back to Brexit 2.0 later. If the party chooses a leader seeking EEA membership, then, fine — we’ll have to face the electorate on immigration. And if the party chooses a leader seeking a clean break from the EU and a new start, we’ll expect Conservative MPs to back that leader or go and form that new party they’ve been threatening.

We can’t go on with May. Bite the bullet, replace her, and fight it out to see what we do next.