The U.S. Navy’s attack on an Iranian frigate, the IRIS Dena, on Wednesday was the first time an American submarine has sunk an enemy ship since World War II. But the Dena may not have been armed because it was returning from an international exercise in the Indian Ocean, and the U.S. Navy likely knew it because it was taking part in the same exercise. Both the United States and Iran were taking part in the MILAN 2026 exercise, organized by the Indian Navy, on February 15–26, with the U.S. s...