Espionage, counterintelligence, and covert action are essential components in the military arsenal of every great civilization. This was especially true for the United States and the former Soviet Union during the Cold War. The need for high-quality intelligence on the enemy’s capabilities was even more critical back then.

Effective counterintelligence operations have played a pivotal role in American history since before the Revolutionary War. Counterintelligence was vital in that conflict against the far more powerful, better-funded and better-organized British army. General George Washington and his fellow compatriots John Jay and Benjamin Franklin engaged in a wide range of clandestine operations that helped turn the tide and gave the colonists a fighting chance against the British – the world’s only superpower at the time.

From The Revolution through World Wars I and II – the need for clandestine espionage in the United States grew exponentially in proportion to the expanding threats she faced. At the Potsdam conference in July of 1945, President Harry Truman was surprised at Soviet Premier Josef Stalin’s cool reaction when he informed the Russian leader that the U.S. had recently acquired “a new weapon of unusual destructive force.” What the President of the United States was not aware of at the time was that Stalin already knew about the atomic bomb project.

In A Spy’s Guide to Santa Fe and Albuquerque by E.B. Held, the author describes how the U.S. Army’s Signal Intelligence Service (precursor to the National Security Agency), began a secret operation in February 1943, later codenamed VENONA. The mission of this project arose initially as a means to examine and exploit Soviet diplomatic communications, but once the program was under way the project was expanded to include espionage and counterintelligence as well.

It took two arduous years before American cryptologists were able to break the KGB codes. Held writes: “The encryption system used by the KGB was referred to as a ‘one-time pad.’ As the name would suggest, one-time pads were supposed to be used only once, which made it virtually impossible for American counterintelligence to break the code and read the encrypted telegrams.” Properly used one-time pads are a totally secure means of communication, even against an adversary with infinite computational power.

As Held points out, however, the pads were sent to and from Moscow via diplomatic pouch, and back then it could take several days or even weeks to complete the trip. The Russians apparently never found out that the delays were intentional. These constant interruptions hampered the KGB’s intelligence efforts and required that they sometimes use their one-time pads multiple times: a critical mistake. Ultimately, U.S. counterintelligence agents were able to gain access to the cyphers through the cooperation of the Western Union office in New York City, the location where all Soviet diplomatic pouches were sent.

The big breakthrough finally came: “When the KGB used their one-time pads more than once, American counterintelligence was able to break the code and begin reading the top secret telegrams (to Moscow).” The information gleaned from this correspondence provided U.S. counterintelligence with valuable insight into Soviet intentions and exposed the treasonous activities of several scientists working on the Manhattan Project.

The VENONA files are most famous for exposing the deeds of Ted Hall, Klaus Fuchs and Julius and Ethel Rosenberg. The files, which weren’t officially released until 1995, provided historians with indisputable proof of their involvement with the Soviet spy ring (code named ENORMOZ).

The first public release of VENONA files by the NSA included messages about the Soviet Union’s efforts to obtain information on U.S. atomic bomb research and the Manhattan Project. Eventually, all of the VENONA files were made public. The documents confirmed the perception of many Americans in the 1950s and 60’s that the communist threat was real and not a fantasy spawned by right-wing paranoia as many on the left had charged. In some ways, the VENONA files vindicate the now-discredited efforts of Wisconsin Senator Joseph McCarthy and the highly publicized ‘Army-McCarthy’ hearings of 1954. McCarthy was eventually censured by the Senate when he was unable to prove his wild claims about communist infiltration into virtually every facet of American life. The VENONA files prove that many of these allegations were justifiable.

In 1949, the name Klaus Fuchs came up in one of the newly-decrypted cables. Emil Julius Klaus Fuchs was born on December 29th, 1911, in Russelsheim, Germany. He studied physics and mathematics at the University of Leipzig. He joined the German Communist Party as a young adult. Fuchs was forced to flee the country when the Nazis came to power in 1933 and expelled the communists. Fuchs moved to the U.K. where he continued his studies and became a naturalized British citizen. His hatred of the Nazis led him to become a spy for the Soviets.

At the start of the Second World War, Fuchs was briefly detained in Britain, but he was soon released when the authorities discovered how useful his knowledge of physics could be to the government.

In 1943, thanks to the clandestine efforts of KGB double-agent Kim Philby, Fuchs was allowed to travel to the United States as part of the British team working directly with the Americans on the Manhattan Project developing the atom bomb. Fuchs did not have the proper security clearances for this assignment because of his communist ties, but master counter-spy Philby made sure that Fuchs was included on the Los Alamos team.

All of the Manhattan Project scientists loved Klaus Fuchs. He was smart, out-going, charming; and he always volunteered to help out when needed. His supervisor, Hans Bethe, later confessed that if Fuchs was a Soviet spy, he “played it perfectly.” Fuchs himself later tried to rationalize his espionage activities as “controlled schizophrenia.”

Fuchs was such a trusted member of the team he was given the task of compiling the entire history of the project – so he knew every detail of its design and construction intimately. Because of his deeply held communist beliefs, he solemnly concluded that a ‘nuclear monopoly’ by the US represented an immoral and potentially dangerous situation for humanity.  Fuchs was not alone in this regard. Several of his associates back in Los Alamos began to share the same opinion. Leo Szilard and James Franck drafted a petition signed by almost 70 scientists who opposed the use of the bomb on moral grounds.

On the second of June, 1945, Klaus Fuchs (code name: CHARLES) met his KGB contact in Santa Fe, New Mexico, and handed him a package of incredibly damaging secrets about the two different processes for separating isotopes of uranium then being explored by Manhattan Project scientists: gaseous diffusion and the electromagnetic method. Held points out that this exchange was, “the single most important intelligence success in KGB history.”

Fuchs’ KGB contact was Harry Gold (code name: ARNO), a Swiss born Russian-Jewish immigrant. Born on December 11th 1910, Gold was a chemist by trade. As a young man, Gold became interested in socialism, which eventually led him to establish contacts within the local communist movement. Gold studied chemical engineering at Drexel Institute and Xavier University in Cincinnati, graduating summa cum laude in 1940. He was recruited into the KGB during this period. In 1940, Gold was activated for Soviet espionage and was assigned the codename GUS, or GOOSE; later ARNO. Harry Gold was a courier for a number of Soviet spy rings during the Manhattan Project.

By 1949, Signals Intelligence was finally making some progress decrypting the VENONA cables. They had identified the code names of four KGB operatives who had worked at the labs during the war: CHARLES, BUMBLEBEE, MLLAD, and PERSEUS. Then they got lucky: “In one secret telegram, the KGB operative inadvertently used the actual name of CHARLES – Klaus Fuchs – instead of his code name.”

In the meantime, Fuchs had returned to England where he was head of the physics department at the British Atomic Energy Research Center at Harwell. High-ranking British double-agent Kim Philby informed his KGB handlers that Fuchs was in potential danger, but Philby’s deep cover could have been blown if either of them took any action to save Fuchs. It was decided to leave him to his fate. Fuchs was confronted by British Intelligence as a result of the decrypted VENONA cables and other evidence that he was a Soviet agent. Fuchs initially denied any involvement when MI5 officers questioned him in December of 1949, but after constant badgering, Fuchs finally broke down and confessed a month later. He was convicted of espionage on March 1, 1950, and sentenced to fourteen years in prison.

Klaus Fuchs was released on June 23rd, 1959, after serving just nine years and four months of his sentence at Wakefield Prison. He immediately flew to East Germany. He died in Dresden in 1988.

Klaus Fuchs’ confession eventually led to the trials of David Greenglass (BUMBLEBEE) and Julius (ANTENNA) and Ethel Rosenberg in the U.S. The Rosenberg’s were both executed for their crimes in 1951.

Fuchs’ testimony and the decrypted VENONA cables led directly to Harry Gold. The FBI arrested him and searched his home. There they uncovered evidence of long-term industrial and atomic espionage being conducted on behalf of the Soviet Union. Like Fuchs, Gold broke down under the pressure of intense questioning. He was given the option of cooperation or death; Gold confessed to everything. He served 16 years of a thirty-year sentence at Lewisburg Penitentiary in central Pennsylvania before being paroled in 1966. Harry Gold died in 1974.

Theodore Alvin (Ted) Hall (code name: MLLAD) was the youngest physicist working on the atomic bomb project at Los Alamos during World War II. He was later identified as a Soviet spy by the VENONA decrypts. Hall graduated from Harvard, where he was a brilliant physicist. He served in the United States Army during World War II.

Ted Hall acquired leftist sympathies early in life, believing that the Soviet ideology was more in line with his political views. He met his best friend, KGB contact Saville Sax, while attending Harvard. The two shared similar political beliefs.

Hall was assigned to work on the Manhattan Project in Los Alamos, helping to develop the atomic bomb. Because of his communist beliefs, he decided that the United States’ unilateral control over atomic bomb technology gave the country too much power. He feared this could lead to potential disaster with no other nation on earth able to serve as a counter-balance. He decided to help the Soviet Union to level the playing field. Hall provided extremely valuable technical information to the Soviet Union about the construction of the device, which saved them several years of research on their own atomic bomb project. Because of his friendship with Sax, Hall decided to make contact with Soviet officials and initiate an information transfer.

E.B. Held claims that the Cold War truly began on May 6, 1945, when Hall provided his friend Sax with vital information “on the critical mass of uranium-235 needed in the Little Boy atomic bomb design that would eventually be used on Hiroshima, as well as a progress report on the implosion technique used in the plutonium-based Fat Man design to be used on Nagasaki.”

U.S. counterintelligence learned of Hall’s espionage activity from the VENONA intercepts. However, because of the need for absolute secrecy, the Americans did not want to alert the Soviets to the fact that they had broken the KGB’s code. Officials confronted Hall but did not pursue any legal action against him. He never confessed.

Hall went on to become a noted biophysicist at Cambridge University. For the rest of his life he steadfastly refused to directly confirm any accusations of espionage. But the release of the VENONA documents in 1995 and 1996 reinforced the case against him.

In a written statement given in 1997, he indirectly admitting to the charges, saying that in the immediate postwar years, he felt very strongly that ”an American monopoly” on nuclear weapons ”was dangerous and should be avoided.”

Hall, suffering with cancer and Parkinson’s disease, conceded that he may have been wrong about the Soviet government, but he refused to apologize for his actions. Hall died two years later in Cambridge, England.

[Repost from 2014]