The general election we’ve all been waiting for has finally been called. The Prime Minister announced the election date – 4 July – in the pouring rain, his suit jacket becoming drenched as he spoke, all while someone blared ‘Things Can Only Get Better’ outside Downing Street. The whole scene was so on the nose, no satirist would have ever thought of staging it. It should be clear already that Rishi Sunak has made a terrible mistake.

Barring a miracle, Sunak is about to lead his party to an historic defeat

The PM has clearly been advised that going early with his election announcement is preferable to being seen to ‘do a Gordon Brown’ and holing up in No.10. The inflation figures yesterday may have also been a factor. But while it’s true that inflation has slowed to 2.3 per cent on the year to April – which marks the lowest headline inflation rate in almost three years – this is hardly something that is going to persuade people to vote Tory.

The inflation stats will not be noticed by anyone who isn’t obsessed with politics already. People will notice inflation lowering when prices seem to be genuinely stabilising for them. This will take longer than the next six weeks to happen. Even if voters feel like inflation really is reducing, they still wouldn’t give a lot of credit to Sunak or Jeremy Hunt for that.

Announcing his snap election so soon after the local elections also looks foolish: the Tories lost more than 470 councillors and control of 10 councils. Many of those councillors will have fought hard for their seats. Had an election been held in May, they could have tried to get out the vote for the Tories in the general election at the same time as they fought in their local contests. But now, having lost their seats, who can blame these campaigners for staying at home?

Perhaps Sunak hopes a summer election might coincide with Brits feeling positive about the future. The European football championships are on during the campaigning period, so the PM might be expecting a boost from people in England who could well be feeling more patriotic than usual.

This looks like wishful thinking, Sport and politics don’t mix well, and it’s hard to see how the thought that ‘England have made it into the quarter finals of a major football tournament’ translates to ‘Perhaps I should vote Conservative after all’. England usually makes the quarter finals of major football tournaments. It also usually loses at this stage. And whether they do so or not has very little bearing on who the country thinks should be in government either way.

Another reason to go to the country now is that Sunak hopes to pull out the rug out from under Reform UK. This, again, seems like an overly optimistic assessment: Nigel Farage will put himself at the centre of the Reform general election campaign, or he won’t. The timing of the election has little bearing on this. If Farage announces today that he is going to be the face of Reform’s campaign, Sunak is in trouble; if he stays out, he was probably always going to do so anyhow.

It’s clear that Sunak should have waited until the autumn, probably November, to call an election. Sure, nothing might have changed between now and then, but you never know. Some international crisis could have come along and given him a better chance of hanging on. But by calling it in six weeks’ time, Sunak has virtually guaranteed that Keir Starmer will be the prime minister of Great Britain and Northern Ireland in a matter of weeks.

The haphazard way in which the PM has begun the campaign tells us much of what we need to know about how miserable the next few weeks will be for the Tories. Standing in the pouring rain while the New Labour theme tune plays behind you is a terrible look that will haunt Sunak.

Barring a miracle, Sunak is about to lead his party to an historic defeat – perhaps one that changes British politics in a profound way for the next few generations. As far as unforced errors go, this may have been the biggest, most consequential one in the history of British politics.