Zohran Mamdani’s stunning win in New York’s mayoral primary has been a tale of two cities, and two Americas. In one, a young man with hopeful, progressive politics went up against the decaying gods of the establishment, with their giant funding and networks and endorsements from Democratic scions, and won. In another, in an appalling paroxysm of racism and Islamophobia, a Muslim antisemite has taken over the most important city in the US, with an aim to impose some socialist/Islamist regime. Like effluent, pungent and smearing, anti-Muslim hate spread unchecked and unchallenged after Mamdani’s win. It takes a lot from...