Yes, German U-boats will attack any ship or vessel going to Britain, without warning. Even if the country that the ship is coming from is neutral.
unrestricted submarine warfare
Germany's unrestricted submarine warfare
Germany practiced unrestricted submarine warfare.
it was Germany.
Order of events that describes changes in Germany's policy of unrestricted submarine warfare:unrestricted submarine warfareAmerican ultimatummoratoriumcancellation of the Sussex Pledge
Germany's submarine warfare was unrestricted. These attacks led to World War I.
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Help end the British blockade
To get the blockade lifted.
it referred to sinking ships
unrestricted submarine warfare
Unrestricted Submarine Warfare.