It has been an explosive weekend for Elon Musk. The American billionaire has had to witness not only the public “rapid unscheduled disassembly” of another of his rockets, but also watch while a group of well-known global companies, including Apple, Disney and IBM, pulled advertising from X, his social media platform. The businesses, all of them household names, made the decision to stop spending on the site, formerly known as Twitter, after the American billionaire’s public support for an antisemitic conspiracy theory. Last Wednesday, Musk replied to a conspiracy post which accused Jews of promoting hatred of white people, noting...