RMS Laconia, carrying 2,732 crew, passengers, soldiers, and  prisoners of war, was torpedoed and sunk by  U-156, a German  U-boat, off the  West African coast.

-> Das Schiff wurde von den Deutschen versenkt. Hast du mit Sicherheit bloss vergessen zu erwähnen. Die Massnahmen erfolgte vor allem, da es sich bei den Schiffbrüchigen um Italiener handelte.

Letztendlich rettete der Angriff Dönitz 1946 den Hals.

The prosecution has introduced much evidence surrounding two orders of Dönitz,  War Order No. 154, issued in 1939, and the so-called Laconia Order of 1942. The defence argues that these orders and the evidence supporting them do not show such a policy and introduced much evidence to the contrary. The Tribunal is of the opinion that the evidence does not establish with the certainty required that Dönitz deliberately ordered the killing of shipwrecked survivors. The orders were undoubtedly ambiguous and deserve the strongest censure.
The evidence further shows that the rescue provisions were not carried out and that the defendant ordered that they should not be carried out. The argument of the defence is that the security of the submarine is, as the first rule of the sea, paramount to rescue and that the development of aircraft made rescue impossible. This may be so, but the [ Second London Naval Treaty] is explicit. If the commander cannot rescue, then under its terms he cannot sink a merchant vessel and should allow it to pass harmless before his periscope. The orders, then, prove Dönitz is guilty of a violation of the Protocol.
In view of all the facts proved and in particular of an order of the British Admiralty announced on 8 May 1940, according to which all vessels should be sunk on sight in the  Skagerrak, and the answers to interrogatories by Admiral Chester Nimitz stating unrestricted submarine warfare was carried on in the Pacific Ocean by the United States from the first day of the  Pacific War, the sentence of Dönitz is not assessed on the ground of his breaches of the international law of submarine warfare

Der Vorfall selbst wurde vom Naval War College (also den Amerikanern selber) folgendermassen eingeordnet.

The Naval War College series International Law Studies covers interpretations of international law during armed conflicts and how these laws were applied by each party. In volume 65, Targeting Enemy Merchant Shipping, chapter three contains an examination of the Laconia incident in the context of the application of international law to World War II submarine warfare:

The person who issued the order to attack and the aircraft commander who carried it out are both prima facie guilty of a war crime. The conduct of the aircraft commander appears to be entirely inexcusable since he must have observed the rescue operation. During the time that they are engaged in such an operation, enemy submarines are no longer lawful objects of attack. The fact that the  US Army Air Force took no action to investigate this incident, and that no trials took place under the then-effective domestic criminal code, the  Articles of War, is a serious reflection on the entire  chain of military command.

Allerdings,

Nach den Regeln der damals gültigen Haager Konventionen waren Lazarettschiffe nur dann vor feindlichen Angriffen geschützt, wenn ihre Namen den Kriegsführenden bekannt gemacht worden waren, ihre Bordwände weiß mit einem Rotkreuz-Emblem gestrichen waren und sie nicht für andere Zwecke verwendet wurden. Voll einsatzfähige Kriegsschiffe mit aufgesteckten Rotkreuz-Fahnen fielen indessen nicht unter diesen Schutz.

Ausserdem sei darauf hingewiesen, dass Dönitz bereits 1939 gegen geltendes Kriegsrecht verstiess

War Order No. 154 - Wikipedia

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