Architects of ABC weapons for the Japanese empire: microbiologists and theoretical physicists
The countries of the Japanese empire, like the Allied and other Axis nations, joined the race to develop atomic, biological and chemical (ABC) weapons during the Second World War. Japanese ABC weapons projects received substantial support from the government of the Japanese empire, with members of the imperial family taking a lot of interest in the programs.1 We see diﬀerent motivations for participation between the scientists-physicists and biologistsinvolved in ABC weapons development. Similarly, the fate and attitudes of these scientists at the end of the war and during the post-war period diﬀered depending on wartime rank, where they were at the end of the war, and whether they were physicists or biologists. Interestingly, their moral values as they pertained to their wartime scientiﬁc activities appear to have remained near constant at an individual level throughout the trans-war period. In other words, imperial wartime rhetoric and pressure failed to change these scientists’ pre-war moral standards. The attitudes of biologists and physicists during the war were diﬀerent from
the start. Japanese biologists involved in bioweapons projects during the Paciﬁc War enthusiastically initiated scientiﬁc research to create and test weapons using available technologies prior to the war and maintained enthusiasm for their projects throughout and after the war. Top-ranked bioweapons oﬃcers such as Ishii Shiro-and Naito-Ryo-ichi actively sold their agenda to the military and ran bioweapons projects, which often included human experimentation. They protected themselves at the war’s end while sacriﬁcing a number of their junior colleagues. After successfully returning to Tokyo from Manchuria, where operations were headquartered prior to the collapse of the Japanese empire, they directly negotiated with SCAP (Supreme Commander for the Allied Powers) oﬃcials such as Lt. Colonel Murray Sanders to obtain immunity from prosecution as war criminals.2 To cover their tracks, oﬃcers such as Yamada Otozo-remained in Manchuria to oversee destruction of evidence related to the Kwantung army’s biological weapons programs. Yamada and others were captured by the invading Soviet Army and put on trial inKhabarovsk to live out their lives under hard labor in Soviet prison camps.