On August 7, 2019, the U.S. Army and Marine Corps published a new manual, The Commander’s Handbook on the Law of Land Warfare [3] ((Army Field Manual (FM) 6-27/Marine Corps Tactical Publication (MCTP) 11-10C), replacing the FM 27-10, The Law of Land Warfare, which was published in 1956. The Handbook “provides a general description of the law of land warfare for Soldiers and Marines, delineated as statements of doctrine and practice, to guide the land forces in conducting disciplined military operations in accordance with the rule of law.” The Handbook sets forth useful explanations of the Law of Armed Conflict, with reference to treaties, customary international law, The Law of War Manual, and other sources. While the Handbook is a useful tool, it does not replace the Department of Defense Law of War Manual and in the event of conflict between the Handbook and the Manual, the latter takes precedence.