WWII pre-nuclear Japanese submarine found off Hawaii coast

A group of scientists found a pre-nuclear Japanese submarine lying off the coast of Hawaii, southwest coast of Oahu.
The said World War II era Japanese submarine is a 400-foot (122-meter), 'Sen-Toku' class vessel. The Sen-Toku type submarine was first proposed by a certain Admiral Yamamoto. It is designed as a stealth unit aimed at shutting down the Panama Canal and also to attack the American West Coast cities.

This particular submarine type had been missing since 1946.

The discovery of I-400 is accidental, said scientist / researcher Jim Delgado. His group was on board a Pisces V deep-diving submersible looking for other items. The mega sub was found lying some 2,300 feet beneath the water surface. (Image: www.steelnavy.com)

For sure, this World War Two Japanese submarine is a national defense and security, highly classified work. If it was treated as a strategic initiative in the 1940s, how much more its improvement would look like these days.