On Aug. 28, France, Germany, and the United Kingdom triggered the U.N. snapback mechanism, leading to the reinstatement of pre-2015 sanctions against Iran last month. Despite Russian and Chinese efforts to stall the process, their draft proposal was rejected by a majority in the U.N. Security Council. With snapback restored, Iran once again faces much harsher restrictions on arms sales, bans on ballistic missile activity, asset freezes, and travel bans. For policymakers in Washington, Brussels,