Between World War I and World War II, the world's naval interest in submarines remained strong. The British, French, and Japanese built improved versions, and during this period the United States Navy built its first large, long-range submarine, the Argonaut. Completed in 1928, it was 381 feet long, had a surface displacement of 2,710 tons, was armed with two 6-inch guns, four forward torpedo tubes, and could carry 60 mines. The Argonaut was the largest non-nuclear submarine ever built by the US Navy, and led to the highly successful American Gato and Balao class submarines used in World War II. In the 1930s, revived Soviet shipyards began mass-producing submarines, especially coastal vessels, to make the Soviet Union a naval power without spending large amounts of money on surface warships. However, while the Soviet program produced a large number of ships, the ships were ill-suited for operation against the German Navy, the crews were poorly trained, and the Sovie...