The United States and Iran are crossing each other's red lines, one after the other. The latest hostilities began with an Iranian drone attack on a cargo ship in the Strait of Hormuz on June 25, a week after they had signed an interim deal aimed at ending the war.

The U.S. and Iran traded heavier strikes Thursday as a weeklong escalation threatened to unravel last month's truce, though Tehran's release of a...

Iran has said it could alert its Houthi allies in Yemen to close another key strait: the Bab al-Mandeb at the mouth of the Red Sea.