I think he recognizes that anti-Semitism is a threat to his personal survival.
With Muslims and Lefties, all religious people who are not Muzzie are in danger. He did a lot to demonize American Christians before he figured out that Hitler was the leader of the National Socialist Party. Commies are not nice to Jews, either. Mass murder comes out of the Left’s centralized power and ideology of group enemies; not out of American constitutionalists (conservatives).