At the close of the First World War, American submarines compared most unfavorably with those of Germany and Great Britain. German submarines sank over 5000 ships, while the British submarine campaign, much less ambitious by design, was still credited with sinking 54 warships and 274 other vessels. Standing in stark contrast, American submarines did not sink a single ship. However, by the end of the Second World War, American submarines would sink over 1300 Japanese merchantmen and warships. This ultimate success was hard won, for attempts to modernize American submarine designs between the wars were continually stifled by advocates of the U.S. Navy\u27s battleship-dominated fleet doctrine, particularly in the 1920s. The major technological obstacle to submarine growth was the development of reliable diesel engines, and an analysis of diesel technology is a cornerstone of this study. The American choice of all-electric propulsion for submarines, unique among major navies of the Second World War, is also explored. Four major factors that shaped American submarine development are identified. They are naval doctrine, technology, organizational dynamics, and the free market
