6th Fleet (Imperial Japanese Navy)
Despite these advantages, IJN submarines achieved remarkably little during World War II primarily having in hindsight suffered from the antiquated strategy of the Imperial Japanese Navy General Staff, who viewed submarines as little more than scouts whose main role was to locate and shadow enemy naval task forces in preparation for a decisive surface conflict. Maybe the IJN General Staff was slow to change as the submarines were generally slow to dive, easy to track with radar and sonar, difficult to maneuver underwater, and less sturdy than their German U-boat counterparts.
Yokosuka Naval Arsenal
The Yokosuka Naval District was established at Yokosuka, Kanagawa in 1884, as the first of the naval districts responsible for the defense of the Japanese home islands, and the Yokosuka Shipyards was renamed the Yokosuka Naval Arsenal in 1903. Japan had purchased five submarines from the American Electric Boat Company during the Russo-Japanese War of 1904–1905. These Holland Type VII submarines were built by Arthur Leopold Busch as he traveled to Japan during this time. Mr. Busch was a naval architect and shipbuilder who represented the newly organized company (Electric Boat Company) now located at the Quincy Massachusett's shipyard known as the Fore River Ship and Engine Company. These first five submarines became Japan's (IJN) initial entry into the theater of underwater warfare that began nearly the same time as the outbreak of the war. Another representative of Electric Boat, Frank Cable, an electrician working for Isaac L. Rice's company trained two Japanese crews in the operation of such craft.