TEHRAN, Aug. 23 -- The man Iran keeps sending for is not a diplomat. Field Marshal Asim Munir runs Pakistan's armed forces, and on Monday he lands in Tehran at the head of an official delegation, having spoken by telephone with Iran's foreign minister only hours before the visit was announced. That is now the shape of the only functioning channel between Iran and the United States: a soldier, a phone call, and a plane.

Esmaeil Baghaei, spokesman for Iran's foreign ministry, made the announcement on Sunday. Field Marshal Asim Munir, the head of the official delegation, will arrive in Tehran on Monday, he said in remarks carried on the ministry's official channel. The visit is meant to strengthen bilateral cooperation and build on what Bag...