U.S. Submarine Sinks an Iranian Warship Off Sri Lanka, Thousands of Miles From the War Zone

On March 4, 2026, the submarine USS Charlotte sank the Iranian navy vessel IRIS Dena in international waters in the Indian Ocean off Sri Lanka, as part of the operation the administration has called Epic Fury. The ship was thousands of miles from the Middle East theater. A source said the submarine took measures supporting search and rescue before and after the sinking, an obligation under the Geneva Conventions.

Legal specialists interviewed about the strike said the vessel would have been a lawful military target had the United States declared war or obtained congressional authorization, and that the legal difficulty lies in the underlying use of force rather than in the choice of target. Brian Finucane, a former State Department attorney-adviser, framed the problem as originating in the absence of authorization; retired Lt. Col. Rachel VanLandingham said Congress should have approved the military action beforehand. Administration officials have argued Iran posed an imminent threat, and have avoided formally describing the conflict as a war.

No congressional authorization for the campaign had been enacted. A House measure to curb further military action against Iran without congressional approval was voted on the following day.