State visits can be uncomfortable, joyful, tense and unifying - in the space of just a few days. King Charles III and Queen Camilla's visit to the United States next month is likely to be all these. Planning the trip has taken months, with decisions about dates and locations being made by Buckingham Palace, the Foreign Office, the Trump administration and the UK Embassy in Washington with its new ambassador, Sir Christian Turner. They are not easy things to get right, as there are many