A U.K. Succession Drama: Who Will Be the Next Ambassador to the U.S.?

In the hectic four-and-a-half years she has served as Britain’s ambassador to the United States, Karen Pierce has overseen a costly renovation of her baronial Washington residence and confronted an American political system in comparable need of repair. The house, at least, is finished.

With Ms. Pierce’s term scheduled to end early next year, Britain’s Labour government now faces a personnel decision that would test the most adroit of diplomats: who to appoint as the next envoy to a country that is a reliable ally but will be on a very different political trajectory, depending on whether Vice President Kamala Harris or former President Donald J. Trump is elected.

Prime Minister Keir Starmer is expected to deal with that uncertainty by not choosing Ms. Pierce’s replacement until after the election in November. That has not stopped the London papers from speculating about who might get what is regarded as the plummiest post in the British diplomatic corps.

Among the names being floated are David Miliband, a former foreign secretary once viewed as a future Labour Party leader; Peter Mandelson, a Labour grandee who has held multiple cabinet posts; and Jonathan Powell, who served as chief of staff to Prime Minister Tony Blair.

“If Kamala Harris wins, he might want a high-profile political ally who can work closely with Democratic leaders,” said Peter Westmacott, ambassador during the comparatively calm years of the Obama administration. “But Starmer tends to prefer substance over personality, so might he prefer a lower-key professional who wouldn’t risk becoming the story?”