In a speech at a special United Nations conference on disarmament on the sidelines of the annual General Assembly session, the new Iranian president sought to portray Iran as a peace-loving nation that has always opposed the militarization of nuclear power, despite suspicions by the United States, Israel and other countries that it is secretly moving toward being able to make nuclear weapons.

It was Mr. Rouhani’s second major speech this week at the United Nations, where he has been engaged in a near-breathless series of appearances and interviews with the Western news media [....]