Civilisational decline happens slowly at first, and then all at once. Britain has not been this weak and irrelevant on the global stage since the early 1500s; France and Germany are facing equally severe existential crises. It took Donald Trump to call our bluff, exposing our impotence and insignificance to a world we once dominated. British and European politicians cannot stop Trump from buying Greenland, or kidnapping Latin American tyrants, or taking out the Mullahs’ evil nuclear programme, or sanctioning Left-wing international judges, or doing whatever else he wants. Eighty-one years after the end of the Second World War, the...