Smiles in the Oval, hugs in Number 10, Sir Keir is a busy man. He might yet be a great one. Of course, the wrecking ball from the White House is spewing lots of risk, but it’s also generating lots of opportunity. For decades, the special relationship between the US and the UK was just about sufficient to keep the UK in line. To varying degrees, successive Prime Ministers from Churchill to Sunak calculated that it was in their interest to tag tight to their bigger cousin in Washington. Famously, in 1944 the future Prime Minister Harold Macmillan captured their…