Venture aloud that the new mayor of New York City, Zohran Mamdani, might just have a touch of the communist about him, and you will run immediately into a wall of indignant pedantry. “He’s not a communist,” his apologists will insist. He’s a “communitarian.” Other preferred substitutions include “collectivist,” “Fabian,” “democratic socialist,” and, in the less intellectually inclined depths of the well, “just, like, someone who cares about other people.” Whatever. A commie by any other name still smells as foul. Besides, far more important than whether Mamdani wishes to be more closely associated with the Judean People’s Front or...