The US says it has killed Islamic State (IS) leader Abu Yusif in Syria.

US Central Command Forces (Centcom) said it carried out an airstrike targeting Yusif – who also goes by Mahmud – in the east of the country.

Another IS operative was also killed in the strike, according to US officials.

This strike was conducted in an area formerly controlled by the Syrian regime and Russian forces.

Centcom commander, general Michael Erik Kurilla, said: “As stated before, the United States – working with allies and partners in the region – will not allow ISIS to take advantage of the current situation in Syria and reconstitute.

“IS has the intent to break out of detention the over 8,000 ISIS operatives currently being held in facilities in Syria.

“We will aggressively target these leaders and operatives, including those trying to conduct operations external to Syria.”

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Consider one view outside the George Washington University Hospital in Washington DC.

“I think we need to paint a mural to Luigi, what do you think?” said one passer-by, with a smile.

“I don’t endorse murder but I think it’s a good thing if CEOs are a little bit nervous.”

Everyone has a thought for the alleged assassin, Luigi Mangione, and it’s not all negative.

Villain or hero? It’s a question dividing America, and not necessarily down the middle.

A quick trawl through the internet reveals Luigi merchandise, Luigi tattoos, “Free Luigi” posters and a fundraiser for Luigi’s legal defence – which has raised $157,225 (£125,492).

Part of the murder response is all about Luigi – the part that bypasses due sympathy for the family and friends of Brian Thompson, the 50-year-old father-of-two gunned down in the street.

He was charged with first-degree murder – later modified to murder as an act of terrorism – after a manhunt that lasted five days.

If the motive was anger with the US health insurance industry, then it’s a sentiment shared.

Americans have long been ground down by the cost of private insurance to gain access to healthcare and the struggle that many face to secure payments.

Claims denied by insurance companies are typically made by people in their darkest hour of urgent medical need. Stories of emotional and financial trauma are legion.

Not that any of that justifies the murder of a healthcare executive on a New York street. Or does it?

I put that question to Sam Beard, organiser of the December 4th legal committee which is raising funds for Luigi Mangione’s legal defence.

He said this: “As a moral matter, it’s a difficult thing to tease out because the same logic has to apply both ways.

“A CEO had his life, tragically and surprisingly to all of his loved ones, cut short, but he was considered an effective CEO exactly because he profited from denying peoples’ claims which cut their lives short.”

“From a simple moral rule, we can’t just apply it without acknowledging that we’re in an immoral system that degrades the value of some human lives while uplifting the value of others. So when we treat this only as a moral act we are plugging our ears to its larger political meaning.

“I’m not in favour of anybody having their life tragically cut short but what I do see as undeniable is that this privatised healthcare system that does cut the lives short of hundreds of thousands of Americans every few years, may be finally getting its reckoning.”

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The adulation attracted by Mangione troubles the authorities in New York, who fear copycat attacks.

Business executives and employees in health insurance have reported being threatened and harassed. “Wanted” posters have also been put up around New York, featuring the CEOs of at least two health insurance companies.

When the indictment against Mangione was unveiled earlier this week, New York City’s Police Commissioner Jessica Tisch emphatically denounced the adulation he has enjoyed.

“This was a senseless act of violence,” she said. “We don’t celebrate murders and we don’t lionise the killing of anyone.”

There’s no doubting the anger felt at the reaction in his favour – but there’s no denying it either.

The post may be seen as glittering and the man as controversial and divisive but beyond those truths, the role of British ambassador to Washington is pivotal and relationship-defining.

That is particularly the case right now: to navigate the “special relationship” through Donald Trump‘s second presidency.

And so this is not a decision that would have been taken without serious consideration despite the baggage some may see Lord Mandelson as carrying.

It follows months of speculation over who could get the job.

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Back last summer, before Trump won the election, a candidate had already been identified by former prime minister Rishi Sunak. He’d given the nod to his national security advisor Sir Tim Barrow, a former ambassador to Russia and the EU.

But then Sunak lost the election. He was out along with his pick. One of diplomacy’s best jobs and Washington’s finest buildings was almost to be Barrow’s, but not quite. What a blow.

Trump’s victory focused minds. It required a particular candidate and doubtless a particular type of character – not necessarily the same type as would have been chosen to navigate a Harris administration.

Lord Mandelson is a political shapeshifter. He is a sharp and agile operator. He is decisive and direct. But he also understands the sensitivities of navigating Trump’s unpredictable and transactional style.

All those traits could be applied to the person Lord Mandelson will take over from.

Dame Karen Pierce became ambassador in 2020 towards the end of Trump’s first term.

A career diplomat, she moved into the role after the previous ambassador, Sir Kim Darroch, was effectively kicked out of America by Trump after a series of less-than-complementary diplomatic cables were leaked.

Dame Karen and her team rebuilt the relationship with Trump’s team and then fostered good terms with the Biden administration with close work on issues like Ukraine.

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And under her leadership the embassy has forged close ties with the incoming Trump administration.

Some view Trump’s presidency as an existential challenge for global diplomacy. Pierce does not see him in quite those terms and nor does Peter Mandelson.

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While an extension of her term was an option for Sir Keir Starmer, sources tell me that it seems more sensible to build on the work she has done with a new ambassador who can get to know the incoming White House team from day one.

His trade background will be seen as vital. It’s a background Pierce doesn’t have. Carving out some sort of trade deal with America at a time when Trump is promising stinging tariffs will be a challenge.

Where Mandelson may fall short is foreign and military policy. In a particularly unstable world, US-UK foreign policy alignment is vital. Mandelson’s experience here does not compare to that of Karen Pierce.

Hours after the Lord Mandelson announcement, embassy staff gathered for their Christmas party in the ambassador’s residence.

No Ferrero Rocher but certainly a nostalgic vibe. Pierce has been diplomatically very effective and is very popular among staff.