belligerent with which it was at peace, the parts of ten submarines Were sent to Canada, where they were put together.
These submarines then crossed the Atlantic under their own power, and were sent from British ports to the Dardanelles, where they succeeded in driving Turkish and German shipping out of the Sea of Marmora. Thus a crossing of the Atlantic by American-built submarines manned by British crews had been accomplished before the Germans made their voyages. It was therefore not necessary for the two German submarines to cross the Atlantic to prove that the thing could be done; but the Germans doubtless believed that this demonstration of their ability to operate on the American coast would serve as a warning to the American people.
We were never at all deceived as to what would be the purpose of such a visit after our entrance into the war. In the early part of 1917 the Allies believed that a few German U-boats might assail our coast, and I so informed the Navy Department at Washington. My cables and letters of 1917 explained fully the reasons why Germany might indulge in such a gesture. Strategically, as these despatches make clear, such attacks would have no great military value. To have sent a sufficient number of submarines to do any considerable damage on the American coast would have been a great mistake. Germany's one chance of winning the war with the submarine weapon was to destroy shipping to such an extent that the communications of the Allies with the outside world, and especially with the United States, would be cut. The only places where the submarine warfare could be conducted with some chance of success were the ocean passage routes which lead to European ports, especially in that area south and south-west of Ireland in which were focussed the trade routes for ships sailing from all parts of the world and destined for British and French ports. With the number of submarines available, the Germans could keep enough of their U-boats at work in these areas to destroy a large number of merchant ships. Germany thus needed to concentrate all of her available submarines at these points; she had an inadequate number for her purpose; to send any considerable force three thousand miles across the Atlantic would simply weaken her efforts in the real scene of warfare and would make her submarine campaign a failure. The cruises of submarines on the
