Open this photo in gallery: On Tuesday night, Elon Musk’s xAI chatbot Grok praised Hitler on its X account.Dado Ruvic/Reuters By the time you read this, someone, somewhere on social media, will have altered the headline, crossing out “antisemitism” to replace it with “Gaza.” And then: “Fixed it for you.” We do need to talk about Gaza, and we are. We will continue to; the horrific death toll and destruction will fill history books. But we also need to talk about antisemitism. I wish I could call what is happening now unprecedented, but it’s the same old hatred, featuring the...