Stop me if you’ve heard this one before. I have told the story elsewhere of my moment of epiphany in understanding the British national character and, in particular, its relationship to irony. My son was being inducted into the Boy Scouts and, as part of the ceremony that parents were invited to attend, the boys played a game. They all stood in a circle around the scoutmaster, who threw a soccer ball in the direction of a boy chosen at random. As he did so, he called out either “head” or “catch.” If he said “head,” the boy was supposed to catch it, and if he said “catch,” the boy was supposed to head it. If the boy caught it in response to “catch” or headed it in response to “head,” he was out, and the game continued until only one boy, the winner, was left. It was great training in the uses of irony, or the principle that meaning depends on context, and perhaps helps to explain why Britons seem to understand this principle instinctively when so many Americans struggle with it.

Everyone in Britain, for instance, instantly understood the meaning of the tweet posted on the November day of an important by-election in the constituency of Rochester and Strood by Emily Thornberry, a Labour Member of Parliament and shadow attorney general, until she was fired for it by Ed Miliband, the Labour leader. The tweet consisted of a photograph of what Americans call a row