What is antisemitism—and why do differences in interpretation matter?

SINCE HAMAS’S terrorist attack on Israel on October 7th, and the outbreak of war in Gaza, there has been a sharp increase around the world in reports of antisemitic incidents. The Anti-Defamation League (ADL), an NGO based in New York City, says that in the two weeks after the attack the number in America quintupled compared with the same period last year. Britain and France have reported similar spikes. Social media have amplified the problem. On X, formerly Twitter, antisemitic posts soared by an astounding 919% the week after Hamas’s attack, compared with a week earlier, as assessed by the ADL. (Islamophobic posts also increased.) Several large companies, including Apple and Disney, suspended advertising on X after a report by Media Matters for America, an activist group, found that ads had been placed next to antisemitic posts. Elon Musk, who owns X, added to the furore when he endorsed an antisemitic post that accused “Jewish communities” of “pushing…hatred against whites.” He has since apologised.