Mayor had said he was reviewing ability to execute arrest warrant issued by the ICC for Israeli prime minister
Archived version: https://archive.is/20260722025149/https://www.theguardian.com/us-news/2026/jul/21/mamdani-benjamin-netanyahu-arrest-authority
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The federal government wouldn’t write a letter though. They’d jump on the opportunity to selectively enforce international agreements against their enemy and point to the pressure from all the other countries as justification.
Better not to risk it for the sake of briefly locking up one guy and instead keep working on things he can affect.