In the days before Germany officially surrendered to Allied forces, the Nazis ordered a U-234 submarine to take whatever remaining weapons and materials were left in their arsenal to Japan. One of the materials that was being shipped was uranium – the essential ingredient for concocting an atomic bomb. The initial plan was to get Japanese engineers to produce a “dirty bomb” that would cause tremendous damage the US West Coast.
In order to actually deliver the makeshift atomic bomb to US soil, the Japanese army would use their armada of 400-foot-long I-400-class submarines. Kamikaze planes painted with US markings were to be launched from the submarine and crashed into Los Angeles and San Francisco. None of their plans came into fruition since the U-234s were captured before they could even deliver their cargo. In the submarines, the US Navy found the uranium that could have potentially altered the ending of the War. The uranium was immediately shipped to the US to keep it away from the Axis.
What’s ironic is that the same uranium that was going to be used to wreak devastation in California was actually used in the Manhattan Project in producing the atomic bombs that would eventually be dropped on Hiroshima and Nagasaki in August 1945. At the time, the US was running low on uranium after numerous tests and blueprint modifications. In the end, the German-made radioactive package was used against Japan to finally end the War.
As for the I-400-class submarines, without additional arms and uranium, they were on schedule to ram into the Panama Canal. The Canal was one of the US’s most important tactical locations during the War since it significantly reduced the sea-travel distance from the states in the East Coast to the Eastern Hemisphere. However, the submarines were scheduled to depart for Latin America on August 17th, a full two days after Japan officially surrendered following the destructive force of two atomic bombs. All of the potential kamikaze submarines were destroyed by the US Navy in order to prevent the Soviet army replicating them.