When a senior Westminster figure finally succumbs to political mortality there is a long-standing parliamentary convention not to speak ill of the dead.

Their successes, not failures, are highlighted. A consensus forms that their resignation – assuming that is the method of their departure – is a noble act, performed in the best interests of the country.

Someone will appear and solemnly quote from Macbeth: ‘Nothing in his life became him like the leaving of it.’

As I write, it appears overwhelmingly likely that tomorrow is the day that – barring a last-minute intervention by his wife Victoria or his own political vanity getting the better of him – Keir Starmer will formally announce his resignation and set out a timetable for his departure. Even if he does try to cling on a few more days, he will soon realise the game is up.

But Starmer does not deserve the usual courtesies.

Sir Keir has been the most disastrous prime minister of the post-war era. He betrayed every single one of the promises he made to the British people. He leaves office with the nation all but defenceless, globally isolated and teetering on the brink of bankruptcy.

He presided over a culture of sleaze, deceit and cover-ups. And rather than exit in a mature and dignified way, he has had to be dragged from office with his fingernails embedded in the famous No10 door post.

Over the next 24 hours his few remaining allies will attempt to construct an alternative narrative around his benighted 24 months in office. Actually, let’s not sugar-coat it. They will lie their posteriors off in an attempt to re-write history.

We will see claims that Prime Minister Starmer was a decent man thwarted by circumstances outside his control.

They will cast him as a giant on the world stage. They will insist, as some have fantastically been stating over the past week, that there is a cruel irony in him being forced to step down ‘just as Britain is starting to turn the corner’.

This is the reality. The man who pledged a cleansing of British politics delivered the Mandelson/Epstein scandal. The man who promised to get to grips with benefits caved to his own MPs and left the country with a spiralling – and unsustainable – welfare bill. The man who promised to stop the boats disowned his own immigration policy a month after it was launched, claiming he hadn’t even bothered to read it.

In the hours and days ahead, pointing out these hard truths will draw allegations of churlishness and spitefulness. But the facts matter. Not least because it’s only by properly understanding why Keir Starmer was such a complete, abject, utter, unmitigated disaster as Prime Minister that his mistakes can be avoided in the future.

I spent much of the last month in Makerfield. It is, economically speaking, quite a diverse constituency, with alternating pockets of poverty and affluence, and a flourishing middle-class living alongside an angry and disillusioned traditional working class Labour base.

But there was one thing that united everyone I spoke to. A visceral, uncompromising loathing of Keir Starmer.

And that loathing came from the same place. A sense of betrayal.

In their eyes, everything Sir Keir had said before the election – on tax, immigration, welfare, the economy – had been a lie.

They understood the problems he was inheriting. They did not expect him to work miracles overnight. They simply asked for one thing. For him to be honest with them about what he intended to do and what he was actually able to deliver.

And that must be the starting point for Andy Burnham, or Wes Streeting, or whoever else picks up Starmer’s accursed chalice. Honesty.

Honesty about the state Britain is actually in as Starmer departs to spend more time with his favourite human-rights charities.

We are not a nation that has turned any corners. We are not a nation where the fundamentals are slowly but surely being put back in place.

Sir Keir leaves office with the country a basket case. We are impotent. We are alone. We have no money. We have no borders. We are divided along lines of race, religion and class to an extent never before seen in our modern history. And the starting point for any national recovery has to be an acknowledgment of the facts.

The other lesson that must be learned from Starmer’s toxic and tortuous term of office is this. Passing the buck is not a political strategy. Blaming ‘the other lot’. Blaming the advisors. Blaming the civil-servants. It is not just an exercise in futility but duplicity.

The British people are not fools. Every time Keir Starmer professed ‘I didn’t know’ they knew full well it was because he had chosen not to bother to ask, because he was scared of the answer.

The final thing Sir Keir’s unfortunate successor needs to grasp is this. His departure does not reset the clock. The two years Starmer has squandered have gone forever. Yes, his replacement will benefit from a short period of goodwill, because the British people remain fair-minded.

But they will not place their desire for radical renewal on hold. Nor will they be placated by Starmer’s old slogan ‘Stability will be the change.’ Or fobbed off with a couple more school breakfast clubs and a crackdown on AI chatbots.

In years to come, the history books will not look kindly on Sir Keir. His allies are attempting to frame him as a sober, serious man who tried heroically but unsuccessfully to guide Britain through the age of Trump and Putin and the AI revolution.

But his allies are wrong. From start to finish his premiership has been an unprecedented, unmitigated catastrophe. And the longer we can all remember that, the better off Britain will be.