Robert Oppenheimer MI5 British Security Service File
55 pages from MI5 British Security Service files covering J. Robert Oppenheimer, dating from March 4, 1946, to March 17, 1954. American theoretical physicist Julius Robert Oppenheimer was the director of the Manhattan Project's Los Alamos Laboratory, during America’s quest to develop the first atomic weapon.
This file contains extracts and summaries of British intelligence gathered on, and communications with American diplomatic agencies about J. Robert Oppenheimer.
Highlights include:
In an October 7, 1953, letter from the American Embassy in London to British Intelligence MI5 agent W. M. T. Magan, embassy legal attaché J. Philip O'Brien writes, "Prior investigation has reflected that Oppenheimer formerly associated with known and suspected Communist Party members. His wife Katherine and his brother Frank have admitted prior CP membership. Allegations have been received indicating that OPPENHEIMER has been responsible for delaying the development of the Hydrogen Bomb."
British intelligence officer P.B. Ray in a December 12, 1953, wrote a note for file that an FBI agent named O’Brien came to him stating that he was under pressure from Washington. Ray noted, "He said he was under pressure from Washington to report on OPPENHEIMER'S activities, particularly as Washington had heard that OPPENHEIMER had visited this country and had then gone on to France. 0'Brien asked if we had any adverse information regarding OPPENHEIMER's visit here. He also asked what degree of coverage we were giving this visit. I told him that action had been taken to alert the security authorities concerned with A.E.R.E. and that we had taken the routine step of asking for a Police report in the event that OPPENHEIMER had come to their adverse notice. Beyond that we had, on present information, no justification for taking any special surveillance action."
