Washington, DC: Recent reporting has revealed that on September 2, 2025, the US Navy launched a missile strike against an alleged drug-smuggling vessel in the Caribbean, killing all but two of the 11 crew members. A second strike then killed the survivors, who were clinging to the overturned wreckage. Do those who authorised and carried out the second strike bear responsibility for a war crime? A legal precedent from World War II says they do.On March 13, 1944, the German submarine U-852 torpedoed the Peleus, a Greek freighter chartered by the British Ministry of War Transport, sinking the vessel. Although most of the 35-man crew initially survived on rafts and debris, members of the submarine subsequently attacked them with machine-gun fire and hand grenades. Only three crewmen lived to recount their harrowing experience.In the wake of this atrocity, the British captured and prosecuted U-852’s commander and four crew members, not for sinking the Peleus, which was a legitimate military target, but for killing the survivors. A military court found all five guilty of a war crime. Three were sentenced to death and executed; two served lengthy prison terms. In rejecting every defence offered by the accused, the court established a firm legal and moral precedent that attacking shipwrecked survivors is a war crime, and that belligerents are obligated to protect those rendered helpless in armed conflict.The court rejected the claim by subordinate crew members that they were following orders issued by their commander, Heinz-Wilhelm Eck. The British judge advocate found that:“The duty to obey is limited to the observance of orders which are lawful. There can be no duty to obey that which is not a lawful order. The fact that a rule of warfare has been violated in pursuance of an order of a belligerent government or of an individual belligerent commander does not deprive the act in question of its character as a war crime, neither does it confer upon the perpetrator immunity from punishment by the injured belligerent.” (Emphasis added.)The judge advocate recognised the limitations faced by soldiers and sailors, stating that “no sailor and no soldier can carry with him a library on international law or have immediate access to a professor in that subject.” But he also emphasised a fundamental truth: “Is it not fairly obvious to you that if, in fact, the carrying out of Eck’s command involved the killing of these helpless survivors, it was not a lawful command, and that it must have been obvious to the most rudimentary intelligence that it was not lawful?”He then not only highlighted to the submarine crew the accountability enforced by military law, but also issued a timeless reminder that adherence to orders cannot supersede legal obligations in warfare: “To fire so as to kill helpless survivors of a torpedoed ship was a grave breach of the law of nations. The right to punish persons who broke such rules of war had clearly been recognised for many years.”The court firmly dismissed Eck’s defense that he needed to clear the wreckage to prevent British naval forces from discovering the submarine’s location and endangering its crew. The judge advocate pointed out that Eck could have used “his speed to get away as quickly as he could.” Instead, “he preferred to go round shooting … at wreckage by means of machine guns.” The judge advocate then pointedly asked: “Do you or do you not think that a submarine commander who was really and primarily concerned with saving his crew and his boat would … have removed himself and his boat at the highest possible speed at the earliest possible moment for the greatest possible distance?”Despite the decisive ruling against Eck and his crew, their actions occurred in the context of a declared war between Britain and Germany, where lethal force and the fear of immediate naval retaliation were realities. The U-boat commander could claim that he acted under the exigencies of combat and a genuine fear for his vessel and crew. By contrast, the September 2025 US strike rested on far weaker factual and legal assertions.The Trump administration claims that drug cartels are effectively at war with the United States, but it has not presented evidence linking those killed to organised criminal groups or organisations. Nor has it credibly defended its claim that the survivors threatened US security, especially given new revelations that the boat was headed to South America, not to the US.True, officials speculated that the survivors sought to right the capsized, burning boat in an effort to salvage the alleged drug haul – assuming that the first strike had not destroyed or sunk the containers. But even if these men – who lacked a radio to call for help – had managed to right the vessel and restart its engines after nearly an hour in the water, they would not have escaped vigilant monitoring by the US Navy. In a subsequent incident, the Navy rescued the survivors of a different missile attack on an alleged drug-smuggling vessel, only to release them to their home countries without charge.The Peleus case set two clear precedents that the Trump administration has seemingly overlooked. First, it affirms that military personnel must refuse to carry out manifestly unlawful orders. Second, it establishes that killing helpless survivors of a wrecked vessel is a war crime. These principles reinforce the duty of accountability and the obligation of armed forces to comply with the laws of war, even amid the uncertainties and pressures of modern operations. The only question now is whether those responsible will be held accountable.Allan J. Lichtman, Distinguished Professor of History at American University, is the author or co-author of several books, including, most recently, Conservative at the Core: A New History of American Conservatism (Notre Dame Press, 2025).Copyright: Project Syndicate, 2025.