His return was almost as uneventful as his voyage out. At the very beginning he had trouble in not being able to rise after an experimental dive. This misadventure was caused by a plug of mud which had stopped up the opening of the manometer. But the difficulty was overcome, and he was able to pass under water between the British ships which were on the lookout. His return home was a triumph. Hundreds of thousands of people gathered along the banks of the Weser, filled with the greatest enthusiasm. Poems were written in his honor and his appearance was everywhere greeted with enthusiastic applause. The Germans felt sure that through the Deutschland and similar boats they had broken the British blockade.
Captain Koenig made a second voyage, landing at New London, Connecticut, on November 1st, where he took on a cargo of rubber, nickel and other valuable commodities. On November 16th, in attempting to get away to sea, he met with a collision with the tug T. A. Scott, Jr., and had to return to New London for repairs. He concluded his voyage, however, without difficulty. In spite of his success the Germans did not make any very great attempt to develop a fleet of submarine cargo boats.
The other German act which brought home to Americans the possibilities of the submarine, the visit of the U-53, was a very different sort of matter. U-53 was a German submarine of the largest type. On October 7, 1916, it made a sudden appearance at Newport, and its captain, Lieutenant-Captain Hans Rose, was entertained as if he were a welcome guest. He sent a letter to the German Ambassador at Washington and received visitors in his beautiful boat. The U-53 was a war submarine, two hundred and thirteen feet long, with two deck guns and four torpedo tubes. It had been engaged in the war against Allied commerce in the Mediterranean. Captain Rose paid formal visits to Rear-Admiral Austin Knight, Commander of the United States Second Naval District, stationed at Newport, and Rear-Admiral Albert Gleaves, Commander of the American destroyer flotilla at that place, and then set out secretly to his destination.
On the next day the news came in that the U-53 had sunk five merchant vessels. These were the Strathdene, which was torpedoed; the West Point, a British freighter, also torpedoed; the Stephano, a passenger liner between New York and Halifax, which the submarine attempted to sink by opening its sea valves but was finally torpedoed; the Blommersdijk, a Dutch freighter, and the Christian Knudsen, a Norwegian boat. The American steamer Kansan was also stopped, but allowed to proceed. When the submarine began its work wireless signals soon told what was happening, and Admiral Knight, with the Newport destroyer flotilla, hurried to the rescue. These destroyers picked up two hundred and sixteen men and acted with such promptness that not a single life was lost.
The action of the U-53 produced intense excitement in America. The newspapers were filled with editorial denunciation, and the people were roused to indignation. The American Government apparently took the ground that the Germans were acting according to law and according to their promise to America. They had given warning in each case and allowed the crews of the vessels which they sunk to take to their boats. This was believed to be a fulfilment of their pledge "not to sink merchant vessels without warning and without saving human lives, unless the ship attempts to escape or offers resistance."
The general feeling, however, of American public opinion was that it was a brutal act. In the case of the Stephano there were ninety-four passengers. These, together with the crew, were placed adrift in boats at eight o'clock in the evening, in a rough sea sixty miles away from the nearest land. If the American destroyer fleet had not rushed to the rescue it is extremely likely that a great many of these boats would never have reached land. The German Government did not save these human lives. It was the American navy which did that. But, technicalities aside, the pride of the American people was wounded. They could not tolerate a situation in which American men-of-war should stand idly by and watch a submarine in a leisurely manner sink ships engaged in American trade whose passengers and crews contained many American citizens.
It was another one of those foolish things that Germans were constantly doing, which gave them no appreciable military advantage, but stirred up against them the sentiment of the world. The Germans perhaps were anxious to show the power of the submarines, and to give America an object lesson in that power. They wished to make plain that they could destroy overseas trade, and that if the United States should endeavor to send troops across the water they would be able to sink those troops.
The Germans probably never seriously contemplated a blockade of the American coast. The U-53 returned to its base and the danger was ended. American commerce went peacefully on, and the net result of the German audacity was in the increase of bitterness in the popular feeling toward the German methods.