Iran ‘Snapback’ Isn’t Worth the Risk

For the U.S., there is one point of high principle worth dying in a ditch for at the United Nations: Never impair the Security Council veto. That’s what President Trump is preparing to do, exacerbating President Obama’s mistakes in negotiating the 2015 Iran nuclear deal.

Mr. Trump rightly withdrew from that agreement in May 2018. The attendant renewal of U.S. sanctions, although imperfectly implemented, brought crushing economic pressure against Tehran. Even so, despite Iran’s continuing violations of the agreement and its…