I've been reading Susan Brigden's biography of Sir Thomas Wyatt. It's dense and interesting but one really interesting modern parallel struck me. Diplomacy becomes all but impossible when one party self image of itself is something that the rest of the world simply doesn't acknowledge or recognize. In this case it's Henry VIII's insistence that he is an orthodox Catholic despite the Break with Rome and the Dissolution of the Monasteries. This puts his ambassadors to the Catholic powers (Wyatt was ambassador to the Emperor) in an impossible negotiating position. This seems remarkably close to the current British government position on Brexit in that there seems to be a belief that the UK can be part of the Single Market while rejecting the bits it doesn't like. Now Henry was a megalomaniac and probably had fallen on his head a few too many times jousting. I'm not sure what May's excuse is.