Here’s a startling fact: There have been eight leaders of the British Labour Party in the past 40 years. Seven of them failed to win a single general election. The exception, Tony Blair, was a Labour politician only in the most technical sense. Leftists saw him as a disguised conservative, a cuckoo in the nest. To this day, Labour activists use “Blairite” as the worst of insults, viler even than “Tory.”

Let’s widen the camera shot a little. All over Europe, traditional parties of the Center-Left have been losing badly. As I write, opinion polls show the French Socialists in fourth place, the Dutch Labour Party in seventh. Greece’s PASOK, the leading party since the early 1980s, is now polling at 7 percent. Spain’s PSOE, which had a comfortable majority as recently as 10 years ago, has been displaced by the more radical Podemos. Social Democrats in former communist countries, such as Poland and Hungary, have, if anything, fared even worse.