This is a carousel. Use Next and Previous buttons to navigate Officials say the man who killed 10 at a Buffalo supermarket this month wrote extensively about “replacement theory,” the conspiracy theory that Jews are systematically replacing white people with Black people. Perhaps the first In 2017 there was a rally in Charlottesville, Va., at which white men wearing khakis and polos, carrying tiki torches, chanted “Jews will not replace us.” When asked about replacement theory, Michael Bloom, executive director of the Jewish Federation Associates of Connecticut, reminded me of Charlottesville. “This is the new reality,” he said. “This is...