NEW YORK, July 22 -- Zohran Mamdani did not hesitate. Speaking publicly on Tuesday, New York City's mayor described Benjamin Netanyahu as "a war criminal" responsible for the deaths of more than 73,000 Palestinians, adding that the Israeli prime minister belongs "in The Hague." The statement was direct, unambiguous, and aimed at a sitting head of government expected to attend September's UN General Assembly in New York.

Donald Trump gave a response. The president declared that Netanyahu "will not be arrested, in any way, shape, or form" while on United States soil. The formulation was categorical. It closed off the ambiguity Mamdani had opened, and made explicit what has been US policy in practice since the International Criminal Court i...