Germany attacked merchant ships as they were not powerful enough to take on warships (battle fleets); they conducted "Guerre de Course" (Commerce Raiding).
Weak naval powers, such as Germany during both world wars, had to revert to "Commerce Raiding" (Guerre de Course) as they did not have a powerful enough surface navy to challenge their enemies on the high seas. Thus their submarines fought primarily merchant warfare; and not fleet actions (Guerre de Escadre).
rules of warfare
The war in Europe was fought on land, in ever-varying terrain, over the four seasons of the year, and against an enemy, who for all their brutality, did fight pretty much in accord of the rules of warfare. The war in the Pacific was fought largely at sea, and otherwise in jungles and steamy little islands, with a whole host of diseases complicating things, and against an enemy that regularly broke the rules of warfare. They were, indeed, two completely different theaters of war.
After WW1, there were strict rules on how much Germany could build their military might.
In the early days of submarine warfare, there were rules that everyone followed when attacking ships. If a submarine was attacking a ship that wasn't obviously a warship, they were supposed to show themselves to the ship, tell them they were going to sink that ship, and then make sure that the crew and civilians were safely off the ship before it was sunk. During World War I, the British had such a large navy that the German navy could not defeat it, and the British were able to stop other ships from bringing food and supplies to Germany. Not only that, but the British could have food and supplies sent to England without much fear of the Germans stopping them. The Germans decided do anything they could to break the British blockade, and to stop food/supply shipments from reaching England. This meant stopping the old rules of using submarines. However, without the old rules for warning ships that they were going to be sunk and making sure the non-military people were safe, this tactic angered countries who weren't involved in the war but had their ships sunk. The USA was one such country...
By engaging in Guerre de Course (merchant warfare) instead of the traditional Guerre de Escadre (Fleet to Fleet sea battles).
Type of naval warfare in which submarines sink vessels such as freighters and tankers without warning, as opposed to attacks per prize rules (also known as "cruiser rules").
The German General Staff did not want the US in the war. After Germany sank the French ship Sussex, Wilson threatened to break off diplomatic relations with Germany, the first step before declaring war, unless Germany agreed to stop the use of unrestricted submarine warfare. The German foreign office agreed to observed the rules of search or visit before attacking enemy ships that were not armed. This, Germany hoped, would appease the US and keep them out of the war.
Weak naval powers, such as Germany during both world wars, had to revert to "Commerce Raiding" (Guerre de Course) as they did not have a powerful enough surface navy to challenge their enemies on the high seas. Thus their submarines fought primarily merchant warfare; and not fleet actions (Guerre de Escadre).
because it remained hidden and fired without warning.
Bradd C. Hayes has written: 'Naval rules of engagement' -- subject(s): Crisis management, Conflict management, Naval tactics, Nuclear warfare
rules of warfare
Prior to WWI, belligerents observed "Prize" or "Cruiser" rules, which stated that the ship couldn't sink a passenger ship, only a merchant vessel of an enemy nation, and that the crew/passengers aboard any vessel must be clear and safe before it was sunk. These rules were from the days of sailing vessels, and with WWI and the advent of submarine warfare and modern weapons, it didn't take long to determine that those rules were obsolete. This was essentially the basis for Germany's initial submarine warfare policy. Though Germany initially tried to comply with Prize Rules, as WWI submarine warfare progressed, it became apparent that those rules were outdated and even dangerous. With its practice of warning ships and allowing passengers and crew to leave prior to sinking, it meant that the attacking submarine would be a sitting duck to any enemy vessels or aircraft. The ship's crew only needed to summon military assistance by radio, and the passengers and crew could take their time to evacuate the ship, giving time for aid to arrive.
Because the German navy was not a strong navy, they had to rely on submarines to attack merchant ships...Guerre de Course (Commerce Raiding).
Well, sub captains couldn't be hanged for piracy on the high seas anymore. Illegal violence at sea is also considered piracy. Attacking unarmed civilian vessels used to be illegal; subs changed all that.
Road Rules - 1994 Mountain Warfare 14-8 was released on: USA: 21 March 2007
Yes. It's just about turned every military person into a law enforcement official. Conventional warfare consisted of rules, uniforms, and governments. Terrorism has NO rules, NO uniforms, and NO government(s).