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why didn't they just run down the jolly roger and surrender?
what is it that caused individuals less than enthused with the nazi regime to put their lives on the line for that regime?
Sometimes, they DID SURRENDER! Before I provide an example... let's examine U-Boat history.
When Germany began building Submarines, "Kaiser Wilhlem" was opposed to Submarine Warfare... because they didn't give the enemy a "fighting chance". (like deer hunters are supposed to give their "game" a "sporting chance"?...

He felt it was "immoral" and "barbaric", to sink an enemy ship and kill ALL of the people on board, without "rescuing" survivors... (or taking prisoners).
Submarine warfare made WAR just that much MORE INHUMANE... and BARBARIC. PEOPLE no longer mattered; and it became "acceptable" to murder hundreds and/or thousands of people, to obtain some "minor" military objective... (What military objective was achieved by the bombing of Nagesaki, after Hiroshima had already been bombed? How many people were killed for the purpose of this bomb "test"?)
Submarines were one of the first Weapons of Mass Destruction... Until Hiroshima, no other war machine could kill as many people at one time, as a Submarine. (with the exception of a few shells from the BISMARK, that sent the unprotected Battleship "BOMB" called the HMS HOOD, and its crew, to the bottom in MINUTES.)
Merchant ships supplying war material to your enemy, and their "escorts" were "fair game" for submarines... Until "someone" decided to put its "mass destruction" capability to use... in the False Flag "Sinking of the Lusitania", which killed hundreds of civilians. It WORKED better than the 911 Attacks, in acheiving its goal of SUCKING us into WWII. The difference between the Lusitania and 911, is that most people never "questioned" the Lusitania sinking.
Because of the BARBARIC INHUMANE MASS MURDER of PEOPLE, by (alledgedly) German Submarines... The British and US Allies began to hunt, and KILL GERMAN SUBMARINES, with an unrestricted VENGENCE!
At the beginning of WWII, GERMAN SUBMARINES "ruled" the North Atlantic. Submarine Crews were the "elite" HEROs of German society when they returned home for new torpedos. Serving on a German Sub at the beginning of WWII was better than being a "Rock Star" or NFL Player is today.
These "GOOD" times came to an end, when long range "anti-submarine" aircraft, closed the "mid-Atlantic gap". Then things went from BAD to WORSE real fast.
If a submarine avoided detection, it became increasingly difficult to communicate with "headquarters", to receive supplies and fuel. All German Subs carried many "secrets", that the Allies were (supposedly) not aware of... The "Enigma" code machine for radio communications was one example... the "snorkel" for running underwater on diesel power, was another... the motor-generator system was yet another... (sub captains were completely unaware that the Enigma Code had been broken early in the War.)
To a German Sub captain, "SURRENDERING" was NOT REALLY AN OPTION! If he surrendered, he would most likely be tortured and/or killed... by ALLIED forces. And if he happened to survived that... the Gestapo, or SS, would be waiting to kill him. And if he survived as POW... how could he ever go home to "Germany" in "disgrace" like that?
The submarine crew has to be "loyal" to the "secrets" contained with the ship. Like the "Norden Bombsight", crewmembers had an "obligation" to protect these "secrets" with their LIVES. Even though EVERYONE might DISAGREE ENTIRELY with NAZI leadership, and favor the assasination of HITLER... they still couldn't SURRENDER the secrets on their ship... to do so, would have VERY NASTY CONSEQUENCES to their families and friends back in Germany.When one assumes "command" of a ship (or aircraft), one also assumes the "responsibilities" that go with it. Every MAN who assumes command of a Submarine, and EVERY MAN who serves on it UNDERSTANDS their "responsibilities" as soon as they set foot on deck.
Back to the original question:
QUOTE
why didn't they just run down the jolly roger and surrender?
what is it that caused individuals less than enthused with the nazi regime to put their lives on the line for that regime?
That's precisely what Captain Hans Langsdorf did when he made the decision to "Scuttle" the German Pocket Battleship "GRAF SPEE" at the "Battle of the River Plate" on Dec 17, 1939...
http://en.wikipedia.org/wiki/Battle_of_the_River_PlateCaptain Langsdorf was from the "old school" German Navy. NO LIVES WERE LOST on any of the Merchant ships that he sank. When the GRAF SPEE became "trapped" in Montivideo it had only 16 hours of fuel left, and 20 minutes of big gun ammo, to "fight" its way out of there. There was no chance of getting back to Germany, or to another port where repairs could be made.
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Ultimately, he chose to scuttle his ship in the River Plate estuary on 17 December, to avoid unnecessary loss of life for no particular military advantage, a decision that is said to have infuriated Adolf Hitler. The crew of Admiral Graf Spee was taken to Buenos Aires, Argentina, where Captain Langsdorff committed suicide on 19 December. He was buried there with full military honours, and several British officers who were present attended. Many of the crew members were reported to have moved to Montevideo with the help of local people of German origin.
His decision saved the lives of more than 1000 of his crewmen. It "bothered" him to expose so many 18 year old seamen to an almost certain death. He had seen enough of that already.
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on October 6, 2007, a street in Ajax, Ontario was named after Captain Langsdorff, this despite protests by some Canadian veterans. Steve Parish, the mayor of Ajax, defended the decision, declaring that Langsdorff had not been a typical Nazi officer. An accompanying picture shows Langsdorff at the funeral of his crew members who were killed in the battle. He is saluting with a naval salute while people beside and behind him, even some clergymen, are giving the Fascist salute.
"You take the High Road; and I'll take the Low Road..." but, I guess that's really a different song...