On Sunday, June 4, 1944, Winston Churchill invited Charles de Gaulle, the leader of the Free French, to lunch on his train along a siding at Portsmouth railway station. The prime minister wanted to brief the general about Operation Overlord, the Allied invasion of France that was scheduled for the next day (but which for reasons of weather had to be put back another 24 hours).

De Gaulle had been a guest of the British for two weeks short of four years, since his brave flight to England during the fall of France, when he had made his famous broadcast of June 18, 1940, announcing that his country would continue the fight against Hitler. Over those years, relations between the most English of Englishmen and the most French of Frenchmen had seen some extraordinary ups and downs, but that lunch was to witness easily the lowest of the downs.

De Gaulle was angry that he was only now learning the details of the invasion plans, with its vast armada of over 5,000 ships and over a million men, but the British, Canadians, and Americans had kept the project on a strict need-to-know basis, and the Free French were felt to be too leaky to be trusted. (Before the raid on Dakar in September 1940, Free French officers had attended dinner in a French restaurant in Liverpool and toasted, “To Dakar!”)

For his part, Churchill assumed that de Gaulle would be so pleased and