In his new book, Presidents at War, Steven M Gillon considers how the second world war shaped a generation of presidents, a span that takes in eight men – but not all of them served in uniform between 1941 and 1945. Gillon likes to “ask people, ‘There are seven men who served in uniform in world war two and who went on to be president: who are they?’ And most people think Jimmy Carter did, and they forget Ronald Reagan.” Carter was born in 1924 and came of age in wartime. But the submariner turned peanut farmer turned politician, who...