Source: Lieber Institute - West Point

Joint legal interoperability in U.S. military practice received little focused attention during recent maritime operations, a deficiency the author experienced firsthand while serving as Staff Judge Advocate to the Commander of the USS Dwight D. Eisenhower Carrier Strike Group during a deployment to the Red Sea that began in late 2023. Five days after departing Norfolk in October 2023 the Carrier Strike Group encountered Houthi missile and drone attacks; over the subsequent nine months the IKECSG expended over 800 munitions, and after the group departed in June 2024 the U.S. Navy deployed five additional carrier strike groups and multiple destroyers to counter Houthi attacks. Operations engaged over 400 Houthi-launched missiles and drones, escorted merchant traffic through the Bab-al-Mandeb Strait, and included 52 days of sustained strike operations led by the Harry S. Truman Carrier Strike Group from March to May 2025.

The combat environment produced recurring legal questions about thresholds for the use of force in self‑defense, who may be defended, the application of customary law as reflected in the UN Convention on the Law of the Sea during hostilities, when the law of armed conflict applies at sea, whether the Houthis qualify as pirates, and how unmanned systems demonstrate hostile intent. Confusion across services about command authority, interpretations of “demonstrated hostile intent” and “imminent threat,” differing service intelligence and culture, and distributed maritime operations sometimes caused delays in action. The author trained subordinate units on the UN Charter, Geneva Conventions, the U.S. Standing Rules of Engagement (SROE), higher headquarters guidance, and commander’s intent, and highlights that joint legal interoperability—distinct from technical or procedural interoperability—is rarely taught in pre-deployment training despite its operational significance and implications for future high‑end, multidomain conflict.