Starmer may have weaponised the Windsors, but soft power is the royals' great asset

As Donald Trump waved his personal invitation from King Charles III to pay a second historic state visit in the Oval Office, there was no disguising his delight before the TV cameras. Keir Starmer had retrieved the letter from his jacket pocket and handed it to the US president with the dramatic flourish of Neville Chamberlain's "I have in my hand a piece of paper" moment. From Trump's gleeful response, there was no doubt: in weaponising the Windsors, the prime minister had played a blinder. Monarchists have long argued the soft power of royalty is among its greatest assets. From…