Do the right thing, damn it.

The Laconia incident was a 1942 incident during World War II when RMS Laconia, carrying some 80 civilians and 268 British Army soldiers, and about 1,800 Italian prisoners of war with 160 Polish soldiers on guard, was struck by a torpedo from a Kriegsmarine U-boat off the coast of west Africa and sank. The U-boat commander, Kapitänleutnant Werner Hartenstein, realized the error and commenced rescue operations, joined by other U-boats. Heading to rendezvous with Vichy French ships under Red Cross banners, the U-boats were attacked by an United States Army Air Forces B-24 Liberator bomber. The event profoundly affected the operations of the German fleet, which abandoned the practice of attempting rescue of civilian survivors under the Laconia order of Karl Dönitz.

[...]

The next morning, September 16, at 11:25am, the four submarines, with Red Cross flags draped across their gun decks, were spotted by an American B-24 Liberator bomber from Ascension Island. Hartenstein signalled to the pilot requesting assistance. Lieutenant James D. Harden of the U.S. Army Air Force turned away and notified his base of the situation. The senior officer on duty that day, Captain Robert C. Richardson III, replied with the order "Sink sub."

[...]

Under the Hague Conventions, hospital ships are protected from attack, but their identity must be communicated to belligerents (III, 1-3), they must be painted white with a Red Cross emblem (III, 5), and must not be used for other purposes (III, 4). Since a submarine remained a military vessel even if hors de combat, the Red Cross emblem did not confer automatic protection, although in many cases it would have been allowed as a practical matter. The order given by Richardson has been called a possible war crime, but the use of a Red Cross flag by an armed military vessel may have been a violation of treaty. It would be a violation under the Geneva Convention of 1949 (II, 44). There is no provision in either convention for temporary designation of a hospital or rescue ship.

The Laconia incident had far-reaching consequences. Until then, as indicated in point #1 of the "Laconia order" (below), it was common for U-boats to assist torpedoed survivors with food, water and directions to the nearest land. Now that it was apparent that the Americans would attack rescue missions under the Red Cross flag, Dönitz ordered that rescues were prohibited; survivors were to be left in the sea.

At the Nuremberg Trials held by the victorious Allies in 1946, Dönitz was indicted for war crimes, including the issuance of the "Laconia order":

Laconia Order

1. All efforts to save survivors of sunken ships, such as the fishing out of swimming men and putting them on board lifeboats, the righting of overturned lifeboats, or the handing over of food and water, must stop. Rescue contradicts the most basic demands of the war: the destruction of hostile ships and their crews.
2. The orders concerning the bringing-in of skippers and chief engineers stay in effect.
3. Survivors are to be saved only if their statements are important for the boat.
4. Stay firm. Remember that the enemy has no regard for women and children when bombing German cities!

-http://en.wikipedia.org/wiki/Laconia_incident

Again, the aims and methods of war seem completely irrational when looked at in the context of common decency. A surfaced submarine with a red cross flag on it asks for your help, and you bomb it. Good thinking. It might have been a trap. You know, the trap where a surfaced submarine....uh.... um.... hold on....