“Trump may be the best thing to happen to Starmer,” says a diplomat, suggesting the brash property tycoon busy upending the world order might be just what the strait-laced prime minister – who’s been dragging in the polls – needs.

One of Labour’s business backers calls it “the PM’s finest hour” – a Remainer leader putting Britain at the heart of international action as Trump rattles the Western world’s cage.

Sir Keir Starmer has certainly been incredibly visible – in the White House, leading a European summit at Lancaster House last weekend, hugging Zelensky, plotting a peacekeeping path with Macron.

It’s hard for the Conservatives and other opponents to compete with the prime minister’s international moves dominating the news.

Moments of crisis like the one we’re living through are often when the public tunes into politics and looks to their leaders. With a shaky global situation, does No 10 look more solid than before?

Some of his colleagues are certain. One government source tells me all the international activity is “almost Blair-esque”, or even a moment like Thatcher and the Falklands which enabled the 80s Conservative prime minister to burnish her reputation and win successive election victories.

Another minister suggests other leaders “get their knickers in a twist” publicly reacting to Trump’s unpredictable comments and actions – “but Keir has spent his whole career dealing with extreme circumstances. What he is able to do is get people to focus on the things that really matter.”

But impressive-looking diplomacy doesn’t mean the UK is getting what it wants – missiles are still falling, overnight again in Donetsk and Kharkhiv. Donald Trump’s commitment to guaranteeing Ukraine’s security, even NATO’s future, is shaky too.

So let’s take a calm look. Polling suggests there has been a nudge upwards for Sir Keir’s personal ratings and for Labour, after a dreadful start in office and a steep, fast drop in the polls.

His government would not be the first to be swept away by the intensity and glamour of global diplomacy which, however difficult or worthy, doesn’t necessarily translate into significant brownie points at home.

Perhaps in these wild times, we’re seeing the prime minister carve out a role as “reassurer in chief”. In political circles it’s long been common to find criticisms of Sir Keir Starmer for, frankly, being a bit dull, and not willing to play the minute-by-minute political game. But with Trump in the White House stoking drama the PM’s colleagues believe his steadiness has become an asset.

And he’s shown willingness to take action – increasing defence spending, albeit after months of pressure, getting European leaders together and drawing up military plans for after a peace deal. A senior government source says: “The global crisis means people looking at us again, and the government has been making an argument that people are responding to: that we have got their backs.”

But aligning yourself with an American president doesn’t always work out. Tony Blair’s chinos weren’t the only thing that became uncomfortable about his relationship with George W Bush.

So while there’s evidence the public are looking at Sir Keir a touch more favourably since his White House trip, as one union leader warns, “for it to count he has to show the same mojo at home”.

Take the row over sentencing this week. Or forthcoming arguments over cutting welfare, which ministers have been falling over themselves to soften the ground for.

But overshadowing everything, priority number one: the grisly state of the economy and getting it to grow.

In around a fortnight Rachel Reeves will be on her feet in Parliament, probably announcing cuts to public spending running to billions. Government sources point to some better statistics on wages, and cuts to interest rates, but Reeves is under enormous pressure to explain how the economy is going to escape the doldrums it has been stuck in for ages.

All the Kodak moments, and grip and grins with international leaders in the world won’t change that. The PM “can walk and talk at the same” time, one ally says. But there are, they acknowledge, “only so many hours in the day”.

Helping Ukraine against Putin’s Russia has a clear moral story the prime minister finds easy to tell, and compelling to try to shape. In contrast, “how do you bring prosperity to the regions? That’s a real puzzle.”

In the next few days, starting with the PM’s right-hand man Pat McFadden in the studio tomorrow, you will see the government try to kick up the pace of what is happening at home. First up – perhaps not a box-office hit – they’ll be looking at making the Whitehall machine work better, including making it easier to get rid of civil servants.

Ministers tell me Downing Street is being run more effectively than before Christmas and has a clearer sense of direction, after early embarrassment over being far less prepared than promised.

Sir Keir chairs regular meetings with individual cabinet ministers in charge of the government’s “missions”. I’m told he “cross-examines” them and their officials – and if their answers aren’t up to snuff, they get called in for another meeting. “He is a very nice man, but he is a hard man too,” one of them confides.

As well as slimming down parts of the civil service, there’ll be more on the government’s plans to cut billions off the welfare bill. Labour will argue it’s for good reason, to help people stuck on benefits – while critics will say it’s a way for the government to save money off the backs of some of the most vulnerable people in the country.

On Thursday, the prime minister is expected to make his own speech in an attempt to weave it all together into a grand narrative about safety abroad and at home. One government source said the last few weeks had galvanised Sir Keir’s thinking on this: when things are uncertain on the international stage, “everything feels a bit wobbly” and domestic security is amplified: you look around and feel your job isn’t secure, your street isn’t safe.

This thinking has been a long time coming. “Security” was a word and concept used by Reeves and Sir Keir in opposition – but recently he’s been making a more ideological argument than those close to him are used to hearing.

As well as making the case that what happens around the world is inextricably linked to what happens at home, he holds that the old international consensus among Western leaders has failed for millions of voters.

That argument was crystallised into a long memo he sent to his cabinet ministers and political team in the middle of February. In it he wrote: “The government’s challenge was to shape this new era. Not to defend institutions that are broken or old ideas that have failed, but to be the voice of working people who more than anything want security in their lives, and a country that is on the up again.”

He wrote that politicians were wrong to think markets had solutions for almost everything. “We were cowed by the market – we came to act as if it always knew best and the state should sit it out.”

He also said governments had failed on immigration, failed to understand the public’s concerns and also – to tell the truth. “We ended up treating all immigration as an untrammelled good. Somehow, politics ended up being too scared to say what is obvious – that some people are genuine refugees and some aren’t; that people coming here to work can be a positive, but that an island nation needs to control its borders.”

Some extracts from the letter have been revealed before. But what is notable, reading the whole document, is the prime minister closes his letter to colleagues with a call to provide “security” for the country, alongside renewing public services. He writes: “Now is our moment to be bigger and bolder – to put pedal on metal on wholescale reform and change our politics and our country. Security and renewal are our twin tasks – we must now deliver them.”

You’ll hear more of that argument from ministers in the coming days – we had a glimpse of it in the studio last Sunday morning too.

The profound uncertainty Donald Trump’s arrival in the White House has given the prime minister a moment to step into the spotlight on the world stage.

And his government is now much more overtly weaving an argument that working to establish security round the world is fundamentally connected to sorting out security at home.

There is a reason why, fresh from all the diplomatic handshakes, Sir Keir was back in the more familiar hi-vis and hard hat announcing defence jobs in Belfast.

No 10 wants you to see and believe that crisis abroad can mean opportunity at home. This spasm in global security has given a prime minister sometimes accused of being a blank page a clearer story to tell.

But in the end, for any prime minister, it is what happens on home turf, not foreign adventures that matter the most. A sceptical public will take a lot of convincing to believe government can improve their situation – make it easier to manage the bills, buy a house, or for their kids to find a decent job.

As as a senior figure in the Labour movement concludes, “he likes the statesman role but the bottom line is, change in people’s lives will be the decider.”

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