Secretary of the Navy John C. Phelan is leaving the administration, effective immediately, the Pentagon announced on Wednesday. Sean Parnell, assistant to the secretary of war for public affairs, made the announcement on X. “On behalf of the Secretary of War and Deputy Secretary of War, we are grateful to Secretary Phelan for his service to the Department and the United States Navy. We wish him well in his future endeavors,” he said. Undersecretary Hung Cao will become acting secretary, Parnell said. The Pentagon did not provide a reason for Phelan’s sudden departure. Cao will assume full acting authority over the Department of the Navy and its Marine Corps component....