From the Smithsonian Channel

This Secret Boat Was Built for a WWII Invasion That Never Happened

Name: This Secret Boat Was Built for a WWII Invasion That Never Happened
Uploaded: 2018-08-21
Duration: 137695
Description: In 2011, declassified CIA documents shed light on a covert government program dating back to WWII. At its center was a submersible craft built for a hypothetical invasion of Japan.

In 2011, declassified CIA documents shed light on a covert government program dating back to WWII. At its center was a submersible craft built for a hypothetical invasion of Japan.

Smithsonian magazine | 2:17