The article that follows is the second instalment of “Who Controls the Platform?”—a multi-part Quillette series authored by social-media insiders. Our editors invite submissions to this series, which may be directed to pitch@quillette.com. Censorship is a tool of repression as old as civilization. And fighting it has always been dangerous: Socrates was sentenced to death in 399 B.C. largely because he refused to pander to a panel of moralizing censors. These days, the punishments tend to be less severe (in Western countries, at least). More commonly, the ancient menace of censorship now takes the form of social opprobrium imposed by online hordes supposedly representing the interests of oppressed minority groups—by which I mean hordes of people claiming, almost always without basis, to speak for these groups while promoting their own narrow political agendas. This censorship effort receives back-office ideological support from scholars promoting “intersectionality” and similar theories, which draw heavily from Marxist and post-Marxist thinking on economics and power relationships. It also encourages adherents to view the world through a lens of “oppression and the need …