The consequences of Hamas’ Oct. 7, 2023, attack and Israel’s war in Gaza have reverberated far beyond the zones of conflict. In the United States, for example, a growing number of people, including some Jewish groups, assert that political leaders are exploiting concerns about antisemitism for their own political goals, from cracking down on academic freedom to deporting pro-Palestinian activists. Debate about the war in Gaza feels fraught in Germany, too, where concerns about rising antisemitism have been used to criticize some Muslim communities. The Holocaust looms over discussions about Israel, with many claiming the country’s sense of historical guilt...