Source: Max Hastings. The Secret War - Spies, Ciphers, and Guerrillas, 1939 - 1945
The betrayal of the Manhattan Project by British and American informants was the most important espionage story of World War II; it made no difference against the Nazis, of course, but it was of tremendous importance for after the war. The greatest intelligence coup for the USSR during WW II strengthened Stalin's strategic position against the U.S. during the early years of the Cold War.
In August 1941, German-born Klaus Fuchs (a passionate dedicated Communist) was recruited in Britain by the GRU (Red Army Intelligence), and Fuchs became a key source for Moscow Centre ("Spy Central"). Soon after Pearl Harbor, Moscow learned from Fuchs (and other sources) that the British had abandoned their atomic research, leaving the U.S. and the Manhattan Project as the only show in town. J. Robert Oppenheimer (the scientific head of the Manhattan Project) unwittingly gave some crucial hints to a Soviet spy while at a social occasion attended by left-wingers; among the tidbits from Oppenheimer were Einstein's letter to FDR in 1939. The NKVD (the precursor to the KGB) gave Oppenheimer the codename "Star", knowing that some of Oppenheimer's closest friends and many acquaintances were left-wingers, and many of them were Soviet spies/informants.
In August 1941, German-born Klaus Fuchs (a passionate dedicated Communist) was recruited in Britain by the GRU (Red Army Intelligence), and Fuchs became a key source for Moscow Centre ("Spy Central"). Soon after Pearl Harbor, Moscow learned from Fuchs (and other sources) that the British had abandoned their atomic research, leaving the U.S. and the Manhattan Project as the only show in town. J. Robert Oppenheimer (the scientific head of the Manhattan Project) unwittingly gave some crucial hints to a Soviet spy while at a social occasion attended by left-wingers; among the tidbits from Oppenheimer were Einstein's letter to FDR in 1939. The NKVD (the precursor to the KGB) gave Oppenheimer the codename "Star", knowing that some of Oppenheimer's closest friends and many acquaintances were left-wingers, and many of them were Soviet spies/informants.
Oppenheimer, after taking a very long time to consider an offer to share what he knew with the Russians, reported the encounter to the military head of the Manhattan Project,
General Leslie Groves. Afterwards, the "approaches" to Oppenheimer were drastically reduced, but not entirely eliminated. In his memoirs, one Soviet spy asserted that Leo Szilard, Enrico Fermi, and Oppenheimer knowingly assisted the NKVD in placing moles in various laboratories associated with the Manhattan Project. The same spy claimed that Oppenheimer requested the services of Fuchs knowing he was a Soviet spy. Both those assertions are most likely incredibly impossible, but since Oppenheimer in 1954 lied about his past associations with Communists, many were (and are) ready to believe the worst about him.
If nothing else, Oppenheimer (like Harry Hopkins, one of FDR's most trusted aids) was guilty of some moronic indiscretions which served, in effect, to be the base equivalent of actually being a Soviet informant. By 1942, Moscow was alarmed that the U.S. had committed so much money and resources to the Manhattan Project. Stalin, far more than Winston Churchill or FDR, grasped the strategic significance of the atomic bomb after World War II, and he was hellbent on finding out as much as possible about what was going on with America's atomic research.
General Leslie Groves. Afterwards, the "approaches" to Oppenheimer were drastically reduced, but not entirely eliminated. In his memoirs, one Soviet spy asserted that Leo Szilard, Enrico Fermi, and Oppenheimer knowingly assisted the NKVD in placing moles in various laboratories associated with the Manhattan Project. The same spy claimed that Oppenheimer requested the services of Fuchs knowing he was a Soviet spy. Both those assertions are most likely incredibly impossible, but since Oppenheimer in 1954 lied about his past associations with Communists, many were (and are) ready to believe the worst about him.
If nothing else, Oppenheimer (like Harry Hopkins, one of FDR's most trusted aids) was guilty of some moronic indiscretions which served, in effect, to be the base equivalent of actually being a Soviet informant. By 1942, Moscow was alarmed that the U.S. had committed so much money and resources to the Manhattan Project. Stalin, far more than Winston Churchill or FDR, grasped the strategic significance of the atomic bomb after World War II, and he was hellbent on finding out as much as possible about what was going on with America's atomic research.
The NKVD intensified their efforts at penetrating locations in the Manhattan Project, and they had more success recruiting spies/informants by appealing to their political philosophies and the sacrifice Russia was making against the Nazis versus bribery and/or coercion. However, the NKVD only had limited success in terms of recruiting scientists. Nonetheless, by July 1943 Moscow Centre had 286 classified U.S. documents on the Manhattan Project, and Russian scientists (most of which didn't want anything to do with the NKVD) were consulted so Moscow could prepare their spies on what questions to ask when the opportunities arose.
By 1943 Moscow was still learning more about the Manhattan Project from British informants compared to American informants. Among those informants in Britain were Klaus Fuchs, but he wasn't the only source of information in Great Britain for Moscow. In early 1944, Moscow gave their intelligence operation the codename "Enormoz".
By 1943 Moscow was still learning more about the Manhattan Project from British informants compared to American informants. Among those informants in Britain were Klaus Fuchs, but he wasn't the only source of information in Great Britain for Moscow. In early 1944, Moscow gave their intelligence operation the codename "Enormoz".
Through 1943, penetration of the most secret plants of the Manhattan Project had proven to be impossible for Moscow, and as a result the NKVD was ordered to run point on the intelligence operation. The first American breakthrough for "Enormoz" came from "Mar", a scientist working for DuPont that forwarded information through his sister-in-law. "Mar" thought the U.S. military, by concealing information about the Manhattan Project from the public, was the equivalent of a criminal entity. "Mar" proved to be a consistent source of technical information for Moscow.
During the Winter of 1943, Fuchs was posted in the U.S., and for a while the USSR had a steady stream of information. By 1944, the USSR was conducting technical espionage on an industrial scale; Moscow wasn't just getting information on atomic bomb research, but also on radar, wireless technology, jet propulsion, and synthetic rubber. After a surprise junket to Britain, Fuchs returned to the U.S. in November 1944 . . . and Fuchs was working in New Mexico. Fuchs kept providing information and all he wanted in return was to have the files the Gestapo had on him destroyed when the Red Army reached Berlin.
During the Winter of 1943, Fuchs was posted in the U.S., and for a while the USSR had a steady stream of information. By 1944, the USSR was conducting technical espionage on an industrial scale; Moscow wasn't just getting information on atomic bomb research, but also on radar, wireless technology, jet propulsion, and synthetic rubber. After a surprise junket to Britain, Fuchs returned to the U.S. in November 1944 . . . and Fuchs was working in New Mexico. Fuchs kept providing information and all he wanted in return was to have the files the Gestapo had on him destroyed when the Red Army reached Berlin.
The amount of intelligence and technical information that Moscow had gathered by January 1945 caused the Kremlin to frantically search for uranium, especially when it was discovered that the U.S. was close to testing its first atomic bomb (The Trinity Test in July 1945 at Alamogordo, NM). Soon, high quality uranium was discovered in Bulgaria near Sofia, which was already in the possession of the Red Army . . . mining immediately started.
By the Spring of 1945, Moscow was receiving a steady stream of intelligence from both British and American spies/informants, but by then U.S. security measures were improving, making it more difficult for NKVD handlers to meet with their sources (among the second-tier sources for Moscow was Julius Rosenberg). Twelve days before the bomb that was used for the Trinity Test was assembled, the USSR had secured descriptions of the atomic bomb from their New York City (Fuchs) and Washington, D.C. stations, and in just four years, the USSR would successfully test their first atomic bomb, ending the four year U.S. nuclear monopoly.
By the Spring of 1945, Moscow was receiving a steady stream of intelligence from both British and American spies/informants, but by then U.S. security measures were improving, making it more difficult for NKVD handlers to meet with their sources (among the second-tier sources for Moscow was Julius Rosenberg). Twelve days before the bomb that was used for the Trinity Test was assembled, the USSR had secured descriptions of the atomic bomb from their New York City (Fuchs) and Washington, D.C. stations, and in just four years, the USSR would successfully test their first atomic bomb, ending the four year U.S. nuclear monopoly.