New Documents Found Pointing To Japan's WWII Atomic Bomb Program

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Seventy years ago, the United States dropped the first of two atomic bombs on Japan. At the time, the US was the only country with nuclear weapons. That wasn’t for a complete lack of effort on the part of other countries, however, and new documents found heap more evidence on Japan having a program of its own.

It’s been known for some time now that Japan had some degree of nuclear weapons research going on during the war. Two main projects are thought to have been undertaken, Operations Ni-Go and F-Go, respectively, but it’s a bit difficult to ascertain how far they actually progressed. The programs were, of course, secret at the time, and many of the documents involved were either destroyed by the Japanese government as the war came to an end or confiscated by the Americans.


But the information recently discovered points to the program not only being real, but advancing to the point of uranium enrichment, Jake Adelstein writes in the Los Angeles Times:

A retired professor at the state-run Kyoto University recently discovered a blueprint at the school’s former Radioisotope Research lab, Japan’s Sankei newspaper and other local media reported recently.

The notebooks were related to research work by Bunsaku Arakatsu, a professor at the university whom Sankei said was asked by the Japanese navy to develop an atomic bomb during the war.

Also found were drawings of a turbine-based centrifuge apparently to be used for the study of uranium enrichment. It was dated March 1945. Another blueprint was found of a centrifuge that a Japanese company, Tokyo Keiki, was producing, with a notation indicating the device was scheduled to be completed Aug. 19, 1945 — four days after Japan announced that it was surrendering.


It appears as if the program was more aspirational than anything else. By 1945, the American Manhattan Project was in full swing, employing over 100,000 people. It managed to compile more than 100 pounds of highly enriched uranium, some of which was eventually used in the Little Boy bomb over Hiroshima.

In contrast, centrifuges used for uranium enrichment were still in the design phase in Japan. Just as well, Japan also had a number of issues obtaining the raw, unprocessed uranium needed to get the program going:

“These drawings are more confirmation of the Japanese atomic bomb effort, something many in Japan do not want to admit,” said Robert K. Wilcox, the L.A. based- author of “Japan’s Secret War: Japan’s Race Against Time to Build Its Own Atomic Bomb.”

Wilcox, who has been researching the program for decades, said Japan’s problem was not a lack of know-how.

“They knew the physics needed for creating the bomb and the engineering needed to build it,” he said. “It was lack of element resources like uranium that was the real problem for them.”


Japan likely would’ve used atomic bombs if they managed to develop them in time, however, a widow of one of the Japanese atomic program’s scientists said.

But while the atomic bombings that ended World War II were horrific, they would have been much worse if more than one country possessed the awesome power of nuclear weapons.


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