Barack Obama extended the olive branch to Iran's leaders last Friday in a videotaped message praising a "great civilization" for "accomplishments" that "have earned the respect of the United States and the world." The death of Iranian blogger Omid-Reza Mirsayafi in Tehran's Evin prison two days earlier was, presumably, not among the accomplishments the president had in mind.

Mr. Obama's solicitous message, timed to the Persian New Year's celebration of Nowruz, met a blunt response from the Islamic Republic's supreme leader,...