I t used to be football managers who measured their time at a club in months. Or even days at Spurs. Anything over two years qualifies you for a long service medal. Now it’s prime ministers. In fact it’s worse than that. Because it’s also people who might one day be prime minister. While some Labour MPs are working out how to get rid of Keir Starmer , others are already plotting how to force Wes Streeting out of office should he jump the gun before Andy Burnham is ready to launch his challenge. Who knows where all this could end? Somewhere in the metasphere. It can’t be long before Liz Truss is no longer our shortest serving prime minister. Long live the lettuce. Even as I write, Zia Yusuf is probably compiling a dossier on Nigel Farage’s mysterious donations so that he can force him out of office sometime in 2030. I think we can take it that no one will be doing the same for Kemi Badenoch as she doesn’t have a prayer of making it to Downing Street.…