British Prime Minister Keir Starmer – buttoned-up, lawyerly, reserved – is not a man prone to effusiveness. But when he sat next to US President Donald Trump in the Oval Office last February, he began to speak like his host. “This is really special,” said Starmer, as he brandished a letter from King Charles III inviting Trump for a second state visit to Britain. “This has never happened before. This is unprecedented… This is truly historic – an unprecedented second state visit.” Starmer’s uncharacteristic gushing showed how his government planned to handle the US president in his second term: play...