The US military’s Central Command stated that a container vessel sailing under the Cypriot flag suffered what it called “significant engine-room damage” after being struck by Iranian forces near the Strait of Hormuz. That attack early Sunday prompted the United States to launch its heaviest round of airstrikes yet against Iran, hitting more than 140 military targets, according to the Pentagon. Iran then struck back by firing on several Gulf countries that host American troops, including Bahrain, Kuwait, Qatar, Jordan, and Oman. Omani authorities rescued 23 crew members from the damaged ship, but one Indian national remains missing. The escalating hostilities are now endangering a temporary nuclear accord signed on June 17, as the crucial waterway—through which roughly one-fifth of the world’s traded oil and gas once flowed—has become the central obstacle to peace negotiations.