In choosing the UK’s new ambassador, Keir Starmer is gambling that the rewards will justify the risks

From Prince of Darkness to deputy prime minister to Your Excellency. It is fair to say that the latest incarnation of the politician with nine lives is not a universally acclaimed appointment. In conversation with a cabinet minister a couple of weeks ago, I brought up the idea of Peter Mandelson becoming the UK’s man in Washington. The minister arched a sceptical eyebrow before saying: “We already have a very good ambassador there.”

There were considerable qualms within government about giving such a pivotal role to one of the most controversial figures in British politics and quite a lot of support for extending the term of the well-regarded Dame Karen Pierce. Sir Keir Starmer was ultimately persuaded that it will take more than the skills of a career diplomat to handle relations with the US during a second Trump term which everyone expects to be a noisy and perilous ride. “I think it is a super smart appointment,” remarks one government loyalist. “My instinct is that Trump respects serious operators and we all know what an operator Peter is.” A friend of Lord Mandelson reports: “He knows what his job is going to be. It is to be the voice of Britain in the president’s ear.” The calculation at Number 10 is that Donald Trump, a man bored by conventional diplomatic types, will be sufficiently intrigued by a figure as vivid as Lord M to pay him attention.