Photo by Leon Neal/Getty Images The ball, right now, is at Keir Starmer’s feet. In a sense, it always is: having the ball is what being prime minister means. But after that dramatic Wexit, with a very shrewdly crafted letter, the question of where to boot it is more immediate. Does he throw himself into a leadership battle against the former health secretary, assuming Wes Streeting gets the numbers for a challenge? I’m assured by a close associate of the Prime Minister that he deeply dislikes Mr Streeting. He thinks he would beat him in a one-to-one contest, as internal Labour polling also suggests, and would greatly enjoy the humiliation of his critic. The trouble is, if a contest starts, the left will also field a candidate – most likely, in the short term, Angela Rayner, but also possibly Ed Miliband, both of whom are likely to beat Starmer. Would that be worth it, for the Prime Minister (a man, I gather, not averse to dirty football tackles) to bring down Streeting?…