Repurposing Armageddon: How the USA planned to use Nazi technology against Japan to end WWII
Uncle Sam had plans to use buzz bombs, nerve gas, and uranium sifted from the ashes of the Third Reich to defeat Japan
World War II in Europe ended on May 8, 1945, but the war in the Pacific did not end until August 15, 1945. During the interval between the surrender of Germany and the surrender of Japan, the USA examined the debris of the Third Reich and tried to extract any material or technology that might prove useful in the Pacific theater of war. The USA had plans to invade the Japanese home islands of Kyushu on November 1, 1945, and Honshu on March 1, 1946, and wanted to use captured German weapons technology during those invasions.
The need for results in a time frame that was expected to be several months, rather than years, focused the American efforts on existing technology that could be very quickly adapted and produced, or existing material that could simply be moved from Europe to the Pacific. The more futuristic German technologies, such as turbojet engines that had short ranges and low reliability, or V-2 rockets that required massive investments in manufacturing exotic and unstable rocket fuel, were not considered to be high priorities for the war effort against Japan.
The first bit of acquired Nazi technology that was en route to the Pacific theater was America’s first cruise missile. The US produced its own versions of the V-1 "buzz bomb" by reverse engineering crashed German cruise missiles. The first attempt resulted in the Jet Bomb One, or JB-1, which used a turbojet engine and was deemed too expensive and unreliable to be mass produced. The JB-2 used a copy of the German pulse-jet engine and was deemed more useful for quickly concluding the war against Japan. The US added a radar transceiver and radar guidance by remote radio control, which improved the accuracy of the JB-2 to about 400 meters or a quarter-mile on average at a range of 160 kilometers or 100 miles, which was a vast improvement over the accuracy of the V-1.
The US produced 1,391 JB-2 missiles, and plans were made to launch them from ships, planes, and land bases constructed on the Japanese home islands after the invasion. The weapon was intended to be used to harass the enemy during periods of bad weather that grounded the B-29 bombers. Crews for the JB-2 were sent to the Pacific theater, but the war ended before the weapons were actually deployed there.
The second product of Nazi technology that was considered for use in the Pacific theater was more sinister. The United States had captured large quantities of German tabun nerve gas: 23,000 tons in aerial bombs and 6,000 tons in 10.5-centimeter projectiles. President Roosevelt had banned the first use of poison gas against Japan. There was not enough gas available in the Pacific to retaliate effectively if Japan used it first, so the German gas was evaluated. It was concluded that only 10-20% of the tabun would disseminate once used, and that the weakened effect was useful for harassment but not retaliation. Testing after the end of the war would reveal that tabun was more lethal than initially assumed and would have been more effective, but the mistaken conclusions of the early tests prevented the nerve gas from being moved to the Pacific in 1945. The nerve gas might have been used if the war had continued into 1946 and Japan had used poison gas against the Allies.
The third product of Nazi tech was the only one that may have actually been used against Japan. On May 14, 1945, the German submarine U-234 surrendered to the USA. The submarine had been bound for Japan with advanced military technology and war material aboard it. There had also been two Japanese officers aboard, but they either committed suicide or were killed by the crew of the sub. When the submarine's cargo was unloaded, approximately 560 kg (1200 pounds) of uranium oxide was discovered. Japan’s atomic bomb program wanted this raw material from Nazi Germany. The material was tested and then sent to the Oak Ridge plant.
The trail of reliable historical documentation on the fate of this material ends there. The very existence of the Manhattan Project was classified as Top Secret at that time, and few documents were made available until decades after WWII. It is believed that the U-235 isotope of uranium was separated from the oxide. German U-235 may have constituted as much as 20% of the amount of uranium in the first atomic bomb that was dropped on the Japanese city of Hiroshima on August 6, 1945. If so, then the final delivery of that uranium to Japan was made by an American B-29 bomber rather than a German submarine.
The grisly repurposing of the technology retrieved from the debris of the Third Reich was never fully completed before the end of the war. Japan could have suffered many thousands of additional casualties if the full potential of this technology and material had been utilized. The modern version of Pandora's box did not release all of its horrors before the end of the war. Fate granted at least a small measure of mercy to Japan by sparing its people from the buzz bombs and tabun. However, the A-bomb dropped on Hiroshima may have been, in some part, the final act of mass destruction inflicted upon humanity by the war machinery of the Third Reich.
https://en.wikipedia.org/wiki/Republic-Ford_JB-2
https://www.thefreelibrary.com/Nerve+gas%3a+America%27s+fifteen-year+struggle+for+modern+chemical...-a0145471038
https://forum.axishistory.com/viewtopic.php?t=167525&start=30
https://www.sun-sentinel.com/news/fl-xpm-1995-12-31-9512300284-story.html
https://military-history.fandom.com/wiki/German_submarine_U-234