Chris Mason: Why Starmer thinks he's called it right on war despite Trump barbs

On nearly every occasion President Trump has found himself in front of a camera in the last few days, he has had a pop at the prime minister and at the UK.

We have long known the current occupier of the White House is rarely a man of subtlety, but the frequency with which he has repeated his criticisms, often unprompted, stands out.

As ever, his language is colourful and quotable.

This is definitely awkward for Starmer, the further souring of his relationship with Trump, but it isn't definitely, wholeheartedly negative from his point of view.

Firstly, there is a tussle over the facts - in other words, precisely what was discussed in the calls between the two men in the last few weeks: what was requested and what was offered.

Downing Street, as ever, is at pains not to get involved in a public mudslinging contest with the White House.

But folk I talk to in Whitehall think the president has garbled some of the details of what the leaders discussed privately.

For instance, I am told there was never a request to provide aircraft carriers in the Gulf, nor an offer to provide them.

British sources also point out that aircraft carriers provide a runway where there otherwise wouldn't be one, but the UK has exactly that on land nearby - at RAF Akrotiri in Cyprus.

I am told there have been just three formal requests from Washington to the UK.

The first was the use of airfields for the initial attacks, which was rejected. The second was the use of those same airfields for defensive purposes when Iran responded by striking its neighbours and that was accepted. And the third was support to ensure the Strait of Hormuz is safe for oil tankers to pass through and that negotiation is ongoing.

They also take issue with the president's characterisation of the prime minister's insistence on consulting his "team." I hear from the Westminster end of things that this was a desire to speak to the British military about what was feasible and to other allies too.

But there is another aspect of things worth exploring here, beyond the formality of Washington's requests, and the informality of the president both in private and in public. I also detect a confidence in the prime minister's conviction that he has called this right.

If you think of the decisions of political leaders like a Venn diagram, often those circles don't do a lot of overlapping. An idea will please some, but not others.

But in this instance, consider this: the prime minister's judgement calls align with his conviction about the parallels between this conflict and the Iraq War two decades ago, which he opposed at the time. He chose to repeat this again in his most recent news conference.

They align too with the importance he attaches to international law, and his view, shared by many but not all, that Israel and America's attacks on Iran were a breach of that law.

Plus they align both with the centre of gravity of opinions among Labour MPs, a rather important constituency for a prime minister who relies on them to keep his job and they align with the centre of gravity of British public opinion.

I struggle to think of many other examples of issues from the prime minister's point of view with this amount of overlapping sentiment.

But yes, there is an elephant in the room: President Trump is of a rather different view and is sharing that view with anyone who will listen. And the frequency with which he repeats his grumble suggests this is a moment he may find hard to forget.

It means that next moment where Sir Keir Starmer and Donald Trump appear in front of the cameras together could be quite the spectacle.

But the prime minister remains of the view that the evidence and the circumstances he is dealing with left him with few other viable alternatives.