Physicist Klaus Fuchs was a quiet, unassuming man who, by a twist of fate, found himself in a position to alter the balance of world power while working at the Los Alamos Laboratory in New Mexico under J. Robert Oppenheimer.
"It is hard to find anything great or admirable in the person of Klaus Fuchs, but the result of his betrayal of our nuclear secrets to the Soviet may have changed the course of history," former CIA chief Allen Dulles writes in Great True Spy Stories.
Fuchs, a German-British scientist, was at the heart of the nuclear programs during WWII, working in the UK, New York, and New Mexico where he helped build the atomic bomb. He leaked every secret he knew to the KGB and may well have remained under the radar if the Allies hadn’t broken the Soviet codes.
The FBI and MI5 suspected Klaus Fuchs of passing Manhattan Project nuclear secrets to Moscow and wanted him neutralized - quickly, and without a scandal - but how? The Venona code-breaking project was top-secret. The Manhattan Project to produce nuclear weapons involved national security, and MI5 couldn’t find any evidence to bring Klaus Fuchs to court. By 1949, the paralysis had created a rift between the Americans and British.
MI5 needed to up its game. They called in William ‘Jim’ Skardon, an ex-Scotland Yard officer turned gentleman spycatcher. He broke criminals by befriending them and offering a shoulder to lean on. It was a charm offensive with a dash of British insouciance, but was Skardon’s patter enough to ensnare a nuclear scientist? The spycatcher would need more than cream tea and country walks to trap his nemesis this time.
"My golden rule of interrogation is" never let a man get away with a lie," Skardon once said. "If he tells one, stop him, let him know that you know. If you let him tell a lie, he's stuck with it. He has to defend it, and then he'll be led further away from the truth."
Klaus Fuchs leaked top-secret intelligence about the Atomic bomb to the Soviet Union
Laying the trap for Klaus Fuchs
The original plan was for Skardon to interrogate Fuchs in London. In November 1949, Fuchs was 37 years old, and the security services on both sides of the Atlantic were flying blind. The Soviet cables suggested Fuchs may have passed atomic intelligence to a USSR contact on one occasion in New York. Neither London nor Washington knew Fuchs had actually been feeding the KGB secrets for seven years.
The young physicist, a communist sympathizer, had left Germany for Britain in 1933 when the Nazis rose to power. Over time, Klaus Fuchs worked on the UK’s atomic bomb project, relocating to the US for the Manhattan Project, and later the Los Alamos Laboratory. By the time Fuchs pinged on MI5’s radar in 1949, he was back in Britain, working at an atomic research center near Oxford and developing Britain’s first nuclear bomb.
Klaus Fuchs wasn’t likely to confess at the initial meeting with Skardon so MI5 fretted about what might happen next. Would Fuchs flee? Contact his KGB handler? What if Fuchs called in the civil servants’ union? That might lead to questions in the House of Commons. Maybe MI5 should arrange alternative employment for Fuchs, perhaps at a leafy university?
An East German institute unwittingly came to MI5’s rescue when it offered Klaus Fuchs’ father a teaching job in the Soviet Zone. The offer made the young Fuchs a potential UK security risk - not a big risk, but MI5 could improvise. It was the perfect cover story for MI5 to book a ‘routine’ interview with Fuchs at his office. The meeting was pushed to December 1949.
Physicist Klaus Fuchs was a quiet, unassuming man who, by a twist of fate, found himself in a position to alter the balance of world power while working at the Los Alamos Laboratory in New Mexico under J. Robert Oppenheimer.
"It is hard to find anything great or admirable in the person of Klaus Fuchs, but the result of his betrayal of our nuclear secrets to the Soviet may have changed the course of history," former CIA chief Allen Dulles writes in Great True Spy Stories.
Fuchs, a German-British scientist, was at the heart of the nuclear programs during WWII, working in the UK, New York, and New Mexico where he helped build the atomic bomb. He leaked every secret he knew to the KGB and may well have remained under the radar if the Allies hadn’t broken the Soviet codes.
The FBI and MI5 suspected Klaus Fuchs of passing Manhattan Project nuclear secrets to Moscow and wanted him neutralized - quickly, and without a scandal - but how? The Venona code-breaking project was top-secret. The Manhattan Project to produce nuclear weapons involved national security, and MI5 couldn’t find any evidence to bring Klaus Fuchs to court. By 1949, the paralysis had created a rift between the Americans and British.
MI5 needed to up its game. They called in William ‘Jim’ Skardon, an ex-Scotland Yard officer turned gentleman spycatcher. He broke criminals by befriending them and offering a shoulder to lean on. It was a charm offensive with a dash of British insouciance, but was Skardon’s patter enough to ensnare a nuclear scientist? The spycatcher would need more than cream tea and country walks to trap his nemesis this time.
"My golden rule of interrogation is" never let a man get away with a lie," Skardon once said. "If he tells one, stop him, let him know that you know. If you let him tell a lie, he's stuck with it. He has to defend it, and then he'll be led further away from the truth."
Klaus Fuchs leaked top-secret intelligence about the Atomic bomb to the Soviet Union
Laying the trap for Klaus Fuchs
The original plan was for Skardon to interrogate Fuchs in London. In November 1949, Fuchs was 37 years old, and the security services on both sides of the Atlantic were flying blind. The Soviet cables suggested Fuchs may have passed atomic intelligence to a USSR contact on one occasion in New York. Neither London nor Washington knew Fuchs had actually been feeding the KGB secrets for seven years.
The young physicist, a communist sympathizer, had left Germany for Britain in 1933 when the Nazis rose to power. Over time, Klaus Fuchs worked on the UK’s atomic bomb project, relocating to the US for the Manhattan Project, and later the Los Alamos Laboratory. By the time Fuchs pinged on MI5’s radar in 1949, he was back in Britain, working at an atomic research center near Oxford and developing Britain’s first nuclear bomb.
Klaus Fuchs wasn’t likely to confess at the initial meeting with Skardon so MI5 fretted about what might happen next. Would Fuchs flee? Contact his KGB handler? What if Fuchs called in the civil servants’ union? That might lead to questions in the House of Commons. Maybe MI5 should arrange alternative employment for Fuchs, perhaps at a leafy university?
An East German institute unwittingly came to MI5’s rescue when it offered Klaus Fuchs’ father a teaching job in the Soviet Zone. The offer made the young Fuchs a potential UK security risk - not a big risk, but MI5 could improvise. It was the perfect cover story for MI5 to book a ‘routine’ interview with Fuchs at his office. The meeting was pushed to December 1949.
Jim Skardon was the UK’s foremost expert on interrogation, although he’d struck out two years earlier trying to get a confession from Ursula Beurton, Fuchs’ KGB handler in Britain. Skardon also failed to close the net around Anthony Blunt and John Cairncross, two Brits later revealed to be KGB spies and members of the Cambridge Five.
Skardon was burnishing his credentials after adopting a smoother, less confrontational interrogation approach, however.
Jim Skardon kept his enemies close
Kim Philby, another Cambridge Five alumni, described Skardon as scrupulously courteous: “His manner verging on the exquisite; nothing could have been more flattering than the cosy warmth of his interest in my views and actions.”
Skardon aimed to win Fuchs’ confidence during the first meeting. They started by discussing Fuchs Sr.'s new job and Klaus' family history. After an hour, Skardon gently made his move: “While you were in New York, I allege that you were in touch with a Soviet official, or a Soviet representative, and passed on to that person information bearing on your work.”
Klaus Fuchs hesitated, polished his glasses, and replied: “I don’t think so.”
After a marathon four-hour interview, MI5’s top interrogator had nothing. Patience was Skardon’s virtue, however. By January 1950, Klaus Fuchs was ready to talk.
The confession
By the time Skardon sat down for his fourth interview with Klaus Fuchs in January 1950, the physicist was ready to talk, eager to justify his actions and salvage what he could. After all, the Soviets were Allies during WWII, so Fuchs wasn’t spying for an enemy.
Although Fuchs spoke for an entire morning, he wouldn’t reveal what he’d done. Skardon decided Fuchs was under considerable mental stress and that an elegant lunch might open the floodgates more quickly than a threat. A trip to the Queen’s Hotel in the historic market town of Abingdon was arranged.
What followed was a confession of such enormity it sent shockwaves through the western world. Fuchs laid out his entire seven-year spying career - right down to how he passed technical details on making the atomic bomb to the USSR. While in England, Klaus would mark page 10 of a magazine, then throw it into a London garden to set up a meeting with the KGB. His Soviet handler responded with a chalk mark on a local lamp post.
In New York, Klaus Fuchs sauntered to his first rendezvous off East Broadway carrying a green book and a tennis ball. A man wearing gloves and carrying a second pair asked him for directions to Chinatown. The man was Harry Gold, a chemist and KGB courier.
Klaus Fuchs also told Skardon how surprised he was that Moscow detonated their first atomic bomb in August 1949 - about two years earlier than expected. MI5 was puzzled about Klaus’ sudden need to unburden himself. Guy Liddell, MI5’s deputy director, wrote in his diary that the confession may have been triggered by a combination of factors: “It is clear that vanity plays a great part,” Liddell wrote. “For two hours, he tried to explain his mental make-up without saying anything about what he had done.”
Before admitting his crime to Skardon, Fuchs had also confided in a work colleague, indicating he felt bulletproof as long as he gave MI5 what they wanted. Klaus Fuchs knew more about building a nuclear bomb than anyone else in the UK. Could Britain really afford to imprison him?
American spies Ethel and Julius Rosenberg were executed
Klaus Fuchs' downfall
FBI director J. Edgar Hoover was furious, accusing MI5 of failing to share reports from Klaus Fuchs’ first three meetings. The New York Times noted: “Fuchs has a long background of communist sympathy which the FBI uncovered with no special difficulty.” Senators asked why Britain vetted a communist sympathizer for a top-secret job and why he was still working for the British government months after his espionage was brought to MI5’s attention.
In February 1950, Klaus received a 14-year sentence for breaching Britain’s Official Secrets Act, the maximum allowed by law. While inside, he met Irish Republican Army prisoner Seamus Murphy. They played chess together and Klaus reportedly helped Murphy escape.
Klaus served nine years before emigrating to Germany where he continued his scientific career. He married Grete Keilson, a friend from his early years as a communist, and died in 1988 at age 77, one year before the fall of the Berlin Wall.
His motives were never firmly established, although Klaus was overheard saying that nuclear weapons should not be owned by one country alone, and that helping the Soviet Union would make the world a safer place.
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