日本核物理学家铃木龙三郎透露说,他和他的许多同事们曾经深信他们在二次世界大战中有可能制造出核武器。甚至曾经有一项向亚洲太平洋岛屿塞班的美军基地投掷一颗原子弹的计划,使他们却步的唯一原因是缺乏资源。那一阶段的关键问题是从铀—238中分离出足够的铀—235。在美国,这种工作是用几种 Ryutaro Suzuki, a Japanese nuclear physicist, revealed that he and many of his colleagues had been convinced that they were likely to create nuclear weapons during the Second World War. Even once there was a plan to throw an atomic bomb at a U.S. base in Saipan, Asia Pacific, the only reason that they were deterred was the lack of resources. The key issue at that stage was the separation of enough uranium-235 from uranium-238. There are several such jobs in the United States