In late 1943, fuchs joined a group of british scientists who traveled to los alamos to work for the manhattan project, and he later passed key information about atomic weapons design to the. In los alamos, fuchs joined the theoretical physics division, where he worked under hans bethe. Rumors of the manhattan project reached japan as well, but, as with germany, no japanese spies penetrated the manhattan project
The Manhattan Project / SamePassage
The soviet union proved more adept at espionage, primarily because it was able to play on the ideological sympathies of a significant number of americans and british as well as foreign émigrés.