Since buying Twitter, rebranded as X, billionaire Elon Musk, who calls himself a “free speech absolutist,” has welcomed hatemongers to the platform, including one who recently coined the trending hashtag #BanTheADL. The ADL, the Jewish Anti-Defamation League, was founded in 1913 during the trial of Leo Frank, a Jewish factory manager wrongly convicted of murdering one of his young workers. After Georgia Gov. John Slaton commuted Frank’s death sentence to life imprisonment, Frank was lynched. Since then, the ADL has aimed to fight antisemitism and secure “justice not only for Jews but for all people.” Musk attacked the ADL on...