The first nuclear bomb of the USSR was a copy of the American one. It was created by atomic spies - a commited communist, an idealistic young man, and a loving husband. Here are their stories

In August 1949, the USSR successfully tested its first atomic bomb and became the second nuclear-armed state. The West was alarmed — the Americans expected that the Soviet Union would not be able to cope with this at least until the mid-1950s. Intercepted and deciphered Soviet intelligence messages revealed a number of spies in the United States and other countries. Some of them were working on the US atomic bomb as part of the Manhattan Project and had access to classified information that they passed on to the USSR. Among them were committed communists, idealists who were against the nuclear monopoly of the USA, and those who just wanted to make some extra money. Some agents were exposed and convicted, while others confessed many years later at the end of their lives. We are telling three of the most vivid stories of atomic spies.

Klaus Fuchs, the communist spy who betrayed everyone

Fuchs was born in Germany to a Lutheran pastor. In 1930, he became a student at the University of Leipzig and, while studying, joined first the Social Democratic and then the Communist Party of Germany. After the Nazis came to power in 1933, Fuchs fled to Britain. There he completed his education and earned a doctorate in physics. In 1940, Fuchs was invited to join the British nuclear project.

After the German attack on the USSR in 1941, Fuchs contacted Soviet intelligence through the USSR embassy and offered to pass on information about the British nuclear program. Fuchs acted purely for ideological reasons — as a committed communist. At a meeting with the agents, he categorically refused the money and asked that this issue never be raised again.

In August 1944, Fuchs joined the “Manhattan Project” as part of the British delegation. He worked in the theoretical physics department and was considered one of the best employees. Fuchsʼs calculations on the splitting of the plutonium nucleus were very important for the creation of the nuclear bomb. He took part in the first bomb test in 1944, analyzed the results of the attacks on Hiroshima and Nagasaki, and, in 1946, joined the development of the hydrogen bomb. The Americans trusted him so much that they even allowed him access to the data that had been withheld from other British scientists.

Fuchs passed this top-secret information to the Soviet residency in the United States under the pseudonym “Charles.” Among all the atomic spies, Fuchs provided the most valuable, complete, and accurate data on US nuclear development. This helped the USSR save at least three years in creating its own atomic bomb.

Fuchs was exposed only in late 1949 with the help of the Venona project. By that time, he had already returned to England and became one of the leaders of the British nuclear program. In early 1950, after several interrogations by British counterintelligence, Fuchs broke down and confessed to everything. “At the time, I had complete trust in Soviet policy and believed that the Western Allies had deliberately allowed the USSR and Germany to fight each other to the death. Therefore, I did not hesitate to provide all the information I had,” he explained his motive. In addition, Fuchs betrayed his contacts in the United States, which led to the conviction of a number of Soviet spies.

At the trial, Fuchsʼs lawyer proved that his crime could not be considered treason, which carried the death penalty. At the time, the USSR was officially considered an ally of Britain and the United States. Fuchs was stripped of his British citizenship and sentenced to 14 years. In 1959, he was released early for good behavior. Fuchs traveled to East Germany, where he spent the rest of his life conducting nuclear physics research. Some researchers believe that Fuchs secretly helped China build its own nuclear bomb in the mid-1960s.

Theodore Hall, the youngest spy who was never punished

In early 1944, Harvard University prodigy physicist Theodore Hall became the youngest participant in the “Manhattan Project”. He was only 18 years old at the time. He helped determine the critical mass of uranium for the “Little Boy” bomb, which was dropped on Hiroshima. Later, he led research on implosion technology for the Fat Man plutonium bomb dropped on Nagasaki.

As Hall later recalled, in 1944, it was already clear that Germany would lose the war and would not have time to develop its own nuclear bomb. He feared that nothing good would come of the American nuclear monopoly. The last straw was when one of the US generals in charge of the “Manhattan Project” began to brag to the scientists that they were actually planning to use the bomb to attack the Soviet Union, then a US ally in the anti-Hitler coalition. After that, one of the physicists left the project in protest, and several scientists began asking government officials not to use such weapons against people.

But Hall decided to act in the spirit of youthful maximalism — to pass on information about US developments to the USSR and thus even the score in the nuclear race. Soviet intelligence had already tried to recruit him at Harvard, so all that remained was to reestablish contacts. In October 1944, Hall took time off work to go home to New York to celebrate his 19th birthday with his family. In New York, he contacted the Soviet residency and passed on information about implosion technology and the design of the plutonium bomb. So it was not least, thanks to Hall, that the first Soviet nuclear bomb, the RDS-1, was very similar in principle and design to the US “Fat Man”.

In June 1946, Hall was dismissed from the “Manhattan Project”. Not because of suspicions of espionage but because of a careless joke in a letter from his older brotherʼs wife. She wrote, “I hear youʼre working on something that goes up with a big bang! Can you send us one of them for Guy Fawkes Day?”

Suspicion of Hall began in the early 1950s when his name and pseudonym, “Mlad,” surfaced in the decrypted documents of the Venona project. Hall was summoned for questioning, but he denied everything. Surveillance and wiretapping of his phone also revealed nothing. So, the FBI decided to stop the investigation, although there were rumors that his older brother Edward Hall had a hand in it. He was a prominent engineer and one of the leaders of the US missile program; in particular, he developed intercontinental ballistic missiles.

Hall peacefully defended his doctorate at the University of Chicago and worked in a laboratory in New York. In the early 1960s, he was lured to Cambridge University, where he became a world-renowned biophysicist. He spent the rest of his life in England. In 1998, a year before his death, Hall gave an interview in which he confessed to espionage: “I decided to give atomic secrets to the Russians because tit seemed to me that it was important that there should be no monopoly, which could turn one nation into a menace and turn it loose on the world as ... Nazi Germany developed. Well, if I helped to prevent that, I accept the charge.” However, they did not try Hall.

David Greenglass, a spy who sacrificed his sister for his wife

In July 1944, David Greenglass, a military mechanical engineer, was sent to work at the Los Alamos nuclear laboratory. In September, he was approached by Julius Rosenberg, the husband of his older sister Ethel. He offered David and his wife Ruth a chance to work for the Soviet Union and meantime earn good money, and they agreed.

Julius and Ethel Rosenberg had been working for Soviet intelligence since the early 1940s. They created an entire spy network codenamed “Volunteers” and recruited US engineers who worked in the military-industrial complex. In addition to information about the “Manhattan Project,” they passed on a lot of other valuable information to the USSR, such as the development of military electronics and radars, drawings of a contactless detonator, and the first American jet fighter, the Lockheed P-80 Shooting Star, which was later used in the Korean War.

Until the beginning of 1946, Greenglass passed on drawings of the plutonium bomb and details of explosive components. He then decided to resign, despite requests to stay with the Los Alamos Laboratory management and, of course, Julius Rosenberg. Greenglass just wanted to be close to his beloved wife. So he returned to New York, opened a small workshop, and lived a quiet family life. In early 1950, the couple was expecting their second child.

Meanwhile, the US intelligence services, with the help of the Venona project, uncovered a Soviet spy network. They were particularly interested in the Rosenbergs. When this was reported to the White House, government officials decided to hold a public trial of the couple. But there was one caveat —the Venona documents could not be used as evidence in court, otherwise the United States would have to admit that it had broken the “super-secure code” of Soviet intelligence. It was necessary for the suspects to confess publicly or for someone to testify against them in court. The arrest of Klaus Fuchs in England unexpectedly helped in this case. He not only confessed to espionage but also turned over his contacts in the United States. And they, in turn, pointed to Greenglass.

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David was arrested in June 1950. He quickly confessed to everything and said that he and his wife had been recruited by the Rosenbergs. Julius was detained in July and Ethel in early August, but they denied all charges. Investigators then offered Greenglass a deal: he would testify against his sister and her husband in a public trial, while his wife Ruth would not face any charges and would return home with their children.

Gringlassʼs testimony became the main evidence against Julius and Ethel Rosenberg, as they never admitted their guilt. They received the most severe sentence — the death penalty. An international campaign was launched to pardon the Rosenbergs. Even Pope Pius XII asked American President Dwight Eisenhower to commute the sentence. But it was all in vain. The Rosenbergs were executed on June 19, 1953, in the electric chair. They remained the only American civilians executed for espionage during the Cold War.

David Greenglass was sentenced to 15 years, of which he served 9.5. His wife and children waited for his release, after which they settled in another area of New York under new names. In an interview in the mid-1990s, David said he had no regrets about his decision: “My wife is more important to me than my sister. Or my mother or my father, okay? And she was the mother of my children, and I love her infinitely.”