For the second time this week, the United States military conducted defensive strikes on Iranian targets as leaders of the two nations continue to negotiate a long-term peace deal.

American forces destroyed a drone ground control station inside Iran’s Bandar Abbas port overnight and shot down four one-way attack drones near the Strait of Hormuz, pushing a week of U.S.-Iran military clashes into dangerous new territory at the chokepoint through which roughly one-fifth of the world’s traded oil flows every day.