Germany's submarine warfare which was introduced in February, 1915, began by sinking less than 50,000 tons of ships per month. By November, 1915, the amount of tonnage destroyed per month was close to 200,000 tons. By January, 1916, the tonnage of ships destroyed by submarines had fallen to under 100,000 tons. In April, 1916, as Grand Admiral von Tirpitz' followers made one more effort to make the submarine warfare successful, nearly 275,000 tons were being destroyed a month. But after the sinking of the Sussex and the growing possibilities of war with the United States the submarine warfare was again held back and in July less than 125,000 tons of shipping were destroyed.
At this time, however, the submarine campaign itself underwent a change. Previously most of the ships destroyed were sunk off the coast of England, France or in the Mediterranean. During the year and a half of the submarine campaign the Allies' method of catching and destroying submarines became so effective it was too costly to maintain submarine warfare in belligerent waters. The German Navy had tried all kinds of schemes but none was very successful. After the sinking of the Ancona the Admiralty planned for two submarines to work together, but this was not as successful as it might have been. During May, June and July the submarine warfare was practically given up as the losses of ships during those months will show. There was a steep decline from a quarter of a million tons in April to less than 140,000 tons in May, about 125,000 tons in June and not much more than 100,000 tons in July.
During these three months the Navy was being bitterly criticised for its inactivity. But as the events six months later will show the German navy simply used these months to prepare for a much stronger submarine campaign which was to begin in August. By this time it was decided, however, not to risk a submarine campaign off the Allied coasts but to operate in the Atlantic, off the coasts of Spain and Norway. This method of submarine warfare proved very successful and by November, 1916, Germany was sinking over 425,000 tons of ships per month.
During this swell in the success of the submarine campaign the U-53 was despatched across the Atlantic to operate off the United States coasts.
U-53 was sent here for two purposes: First, it was to demonstrate to the American people that, in event of war, submarines could work terror off the Atlantic coast. Second, it was to show the naval authorities whether their plans for an attack on American shipping would be practical. U-53 failed to terrorise the United States, but it proved to the Admiralty that excursions to American waters were feasible.
On February 1, when the Kaiser defied the United States by threatening all neutral shipping in European waters, Germany had four hundred undersea boats completed or in course of construction. This included big U-boats, like the U-53, with a cruising radius of five thousand miles, and the smaller craft, with fifteen-day radius, for use against England, as well as supply ships and mine layers. But not all these were ready for use against the Allies and the United States at that time. About one hundred were waiting for trained crews or were being completed in German shipyards.
It was often said in Berlin that the greatest loss when a submarine failed to return was the crew. It required more time to train the men than to build the submarine. According to Germany's new method of construction, a submarine can be built in fifteen days. Parts are stamped out in the factories and assembled at the wharves. But it takes from sixty to ninety days to educate the men and get them accustomed to the seasick motion of the U-boats. Besides, it requires experienced officers to train the new men.
To meet this demand Germany began months ago to train men who could man the newest submarines. So a school was established--a School of Submarine Murder--and for many months the man who torpedoed the Lusitania was made chief of the staff of educators. It was a new task for German kultur.
For the German people the lessons of the Lusitania have been exactly opposite those normal people would learn. The horror of non-combatants going down on a passenger liner, sunk without warning, was nothing to be compared to the heroism of aiming the torpedo and running away. Sixty-eight million Germans think their submarine officers and crews are the greatest of the great.
When the Berlin Foreign Office announced, after the sinking of the Sussex, that the ruthless torpedoing of ships would be stopped the German statesmen meant this method would be discontinued until there were sufficient submarines to defy the United States. At once the German navy, which has always been anti-American, began building submarines night and day. Every one in the Government knew the time would come when Germany would have to break its Sussex pledge.