Soviet atomic intelligence and British disinformation

Did the Soviets have substantial penetration of the Manhattan Project?

Clarke acknowledges genuine spy networks but argues that British disinformation made the overall extent of Soviet knowledge uncertain.

Clarke distinguishes genuine Soviet spy networks from British efforts to feed Soviet intelligence misleading information. He compares deception surrounding the atomic project with similar activity around Enigma. His interpretation leaves the extent of Soviet knowledge uncertain, suggesting that even British officials may not have known exactly how much Moscow understood.