The following extract is taken from my book, "The Innocence of Kaiser Wilhelm II":
"...following the establishment of the ‘starvation blockade’, Admiral Tirpitz and his fellow commanders saw no alternative but to retaliate in kind by preventing supply ships from carrying goods to Britain. U-boat captains were ordered to stop and search British merchant vessels, and, after giving due warning to enable to crews to escape into lifeboats, to sink them with torpedoes. Initially, this was carried out in a genteel fashion, for, as one American commentator wrote:
“The submarines…not only gave time to lower boats but frequently took them in tow and brought them to safety. When the German auxiliary cruisers took aboard the crews and passengers of vessels, they treated them with kindness and humanity. This is proof against the theory of barbarity and cruelty attaching itself to her maritime warfare.”[i]
Britain’s First Lord of the Admiralty, unhappy with this gentlemanly arrangement, which allowed for the loss of so many merchant ships, issued orders that the crews were not permitted to abandon their vessels, but rather should ram the flimsy submarines or – since much of the merchant fleet had been secretly armed – should open fire upon them. This policy made it impossible for the U-boat commanders to continue to assist the enemy crews without risking the lives of their own men, leaving them no alternative but to sink without warning any British ship that they encountered.
Churchill then issued another illegal order that the merchant marines should paint over the names of their vessels and fly the flags of neutral countries to avoid torpedo attacks. Moreover, he manned some of the merchant fleet with Royal Naval officers disguised as foreign fishermen or civilian sailors, so that, whenever a submarine surfaced, the seemingly innocent trading boat was instantly transformed into a lethal warship.
Due to this deceit, and contrary to his own wishes, in February 1915 the Kaiser was persuaded to sign an order declaring unrestricted submarine warfare, meaning that any vessel sailing in British waters, including the English Channel, would be deemed a legitimate target for the U-boat commanders. Wilhelm’s reluctance to authorise this policy stemmed partly ‘from feelings of humanity’[ii], and partly from his fear that it would alienate neutral countries – particularly the United States.(copyright Christina Croft 2015)