себе для памяти. может, найдётся время прочитать текст полностью. пока одна цитата об эффективности подводной войны:
<...>the Japanese spent at least 42 times more on Anti-Submarine Warfare and in losses attributed to submarines than the U.S. spent on her Submarine Force. When one considers the fact that the Japanese economy was only 8.9% of the size of the U.S. economy in 1937, the submarine campaign was clearly an extraordinarily cost efficient means to employ U.S. forces against Japan.
Results of the German and American Submarine Campaigns of World War II