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Disputed reports about the nuclear program in Konan in 1945
Very little is known about the size of the atomic program in Konan though it is conventionally thought to have been small in comparison with the successful U.S. effort. In 1946, a journalist named David Snell working for the Atlanta Constitution wrote a sensationalist story which indicated that Japan had in fact successfully developed and tested a nuclear weapon in Konan. Snell was a former reporter, soon to become Life Magazine correspondent assigned to the 24th Criminal Investigation Detachment in Korea. He interviewed a Japanese officer who said he had been in charge of counter intelligence at the Konan project before the fall of Japan.
According to the officer, who used a pseudonym in the article because he was afraid of retaliation by occupation forces, the program was able to assemble a complete nuclear weapon in a cave in Konan and detonate it on August 12, 1945 on an unmanned ship nearby. Reportedly, the weapon produced a mushroom shaped cloud with a diameter of about 100 m (the first American bomb, "Trinity", had a mushroom cloud some three times the size of that), and also destroyed several ships in the test area. To the observers 20 mi (32 km) away, the bomb was brighter than the rising sun. The officer then claimed that the Russian Army, which captured Konan in November 1945 after some of the last fighting in the war, dismantled the Japanese project and shipped it and some of its scientists taken prisoner back to the Soviet Union.
Most mainstream historians dispute that the Japanese program got close to developing an atomic bomb but US intelligence took the possibility very seriously and continued to question repatriated Japanese from the Konan area about the project.
A 1985 book by Robert Wilcox reprinted the Snell interview as a basis for investigating the Japanese WWII nuclear efforts. In addition to detailing the known Japanese army and navy efforts, the book cites numerous intelligence reports and interviews which indicated the Japanese might have had an atomic program at Konan. It also gave evidence that the Japanese navy, taking up the atomic project after Nishina’s Riken had been destroyed, increased the Japanese efforts to make a weapon. The book, prefaced by Derek deSolla Price, Avalon professor of the history of science at Yale University, who endorsed it, was both panned and praised. Price wrote, “No longer can we maintain that a Japanese bomb just couldn’t have happened. Obviously it ‘nearly’ did. The only questions are how near and what does it do to our judgment on the one case we have of atomic warfare.” James L. Stokesbury, author of A Short History of World War II, wrote: “I had no idea the Japanese were working as seriously on an atomic bomb...this has to modify our perception of one of the crucial issues of the war.”
A review by a Department of Energy employee in the journal Military Affairs degraded it:
Journalist Wilcox' book describes the Japanese wartime atomic energy projects. This is a laudable, in that it illuminates a little-known episode; nevertheless, the work is marred by Wilcox' seeming eagerness to show that Japan created an atomic bomb. Tales of Japanese atomic explosions, one a fictional attack on Los Angeles, the other an unsubstantiated account of a post-Hiroshima test, begin the book. (Wilcox accepts the test story because the author [Snell], "was a distinguished journalist"). The tales, combined with Wilcox' failure to discuss the difficulty of translating scientific theory into a workable bomb, obscure the actual story of the Japanese effort: uncoordinated laboratory-scale projects which took paths least likely to produce a bomb. In the historical journal Isis, two historians of science said only of Wilcox's work that his thesis stood "on the flimsiest and most unconvincing of grounds," and surmised that the hidden agenda of such conspiracy theories was "to furnish a new exculpation for America's dropping of atomic bombs on Hiroshima and Nagasaki."
