What an extraordinary own goal.

Like so many of the clearest, most stark stories, two pictures do almost all of the talking.

For days, the leaders’ teams for the Conservatives and Labour had been telling me things would be different on Wednesday and Thursday of this week.

Politics would take a backseat, the focus would be on the D-Day commemorations.

It did, and it was.

Until that is, it wasn’t.

Rishi Sunak’s decision to leave the most photographed, remarked upon and most poignant event in Europe early was always likely to be spotted.

And so it was, with the bloke who did his job eight years ago, Lord Cameron, playing ‘I’m not a leader’ gooseberry in a photo with three actual leaders – the presidents of the United States, and France and the Chancellor of Germany.

Rishi Sunak was instead hurtling back to the UK to get stuck back into campaigning – recording a lengthy interview with ITV.

We know that because ITV released an extract of it last night, in which the prime minister insisted he hadn’t lied about Labour’s tax plans.

Yes, that’s right – the prime minister left D-Day events early in order not to apologise for misleading claims about his opponents, only to apologise for leaving early in the first place.

Labour, inevitably, are leaping on this, and pointing out Sir Keir Starmer stayed until the end.

And the details matter here because Rishi Sunak was involved in the vast majority of the commemorations.

Alongside the King and Sir Keir, Mr Sunak was at the British event at Ver Sur Mer.

But he wasn’t at the event later at Omaha Beach.

That is where Sir Keir was pictured with the Ukrainian President Zelensky.

A Labour source told me: “What does it say about his judgement that he got this one so badly wrong? It should have been blatantly obvious there was only one place to be yesterday,” adding: “It’s just more desperate stuff. Shows the chaos they’re in.”

Of course, they would say that wouldn’t they?

But about-turns and unequivocal apologies like this are very rare – particularly in election campaigns.

There are many questions about exactly how the situation – which the Conservatives now accept was a cock-up – actually happened.

Whose idea was it that the prime minister would leave early?

Here are a few things I have managed to piece together.

At the end of May, the French government told the BBC that “Rishi Sunak’s presence is not guaranteed at the international ceremony, as the British ceremony will be held beforehand.”

It is the international ceremony that Mr Sunak missed.

I understand from British sources that the itinerary for Thursday was arranged six to seven weeks ago – before the election was called, although at a time when clearly the prime minister must have been thinking about it.

In other words, the plan all along was to miss that final event – and so, the claim goes, the decision to come back early wasn’t driven by doing the interview with ITV Mr Sunak recorded when he got back.

Whatever the motivation, they now admit it was a cock-up – and one that feels like quite a moment in this election campaign.

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