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TLS: Review: Splitting Atoms: Klaus Fuchs

TLS: Review: Splitting Atoms: Klaus Fuchs

Biography|Book Review
Splitting atoms
The man who gave nuclear secrets to the Russians
By Michael Holzman

February 28, 2020

The treachery and pursuit of the most dangerous spy in history

Emil Julius Klaus Fuchs (1911–88) was a theoretical physicist, educated in Germany and in Britain, whose speciality, the mathematical description of sub-atomic matter, became central to the development of the atomic bomb, nuclear reactors and fusion. His father, Emil Fuchs, was a prominent Lutheran pastor, who became associated with the Quakers. Emil Fuchs instilled in his children the precept that they should always do what they believe to be right, without regard to convention or the opinions of others.

While at the University of Leipzig, then at Kiel, Klaus Fuchs became politically active in the dying days of the Weimar Republic, going through the Social Democratic Party, and then the German Communist Party (KPD). After the Reichstag fire he escaped to Paris with the assistance of the KPD and then on to England, where he completed his PhD at the University of Bristol and engaged in further studies at Edinburgh, under Max Born, a fellow refugee. Born, who compared Fuchs to Werner Heisenberg among his students, collaborated with him on a number of papers. Interned as an “enemy alien”, then quickly released after the intervention of prominent scientists, Fuchs became an assistant to the physicist Rudolf Peierls, and was taken up by Peierls’s family.

Fuchs’s work on the separation of uranium isotopes through the gaseous diffusion method brought him to the centre first of the British Tube Alloys programme then that of the Manhattan Project, where he and Peierls were assigned to Hans Bethe’s theoretical physics implosion unit. At Los Alamos, in addition to his continuing relationship with the Peierls family, Fuchs was particularly close to Richard Feynman and Edward Teller. With John von Neuman and Teller, Fuchs began to lay the theoretical foundations of the hydrogen bomb. After the war he was recalled to England. He was made head of the Theoretical Physics Division of the Atomic Energy Research Establishment at Harwell, near Oxford, helping lead the development of the British atomic bomb and nuclear reactor projects and continued work on fusion. But he was arrested in 1950 for espionage, convicted and imprisoned for nine years. After his release he emigrated to the German Democratic Republic, where he resumed his research and administrative activities as deputy director of the Institute for Nuclear Research in Rossendorf, near Dresden.

Frank Close’s new Life of Klaus Fuchs is the fourth to be published in English. These successive biographies have appeared seemingly in rhythm with the releases of files from the National Archives in London (a process which has very recently gone into reverse, as many of those have been withdrawn without explanation). Historians are rightfully in thrall to archives, but they must at least attempt to balance the stories whispered from the files preserved there with other stories. The files originated by MI5 and, to a lesser extent, those of the FBI, determine the shape and emphases of Close’s book more thoroughly than those of its predecessors. Although the focus is on Fuchs, the Trinity of the title refers not only to the codename for an American nuclear test explosion, but also the interaction of the book’s three subjects: Peierls, Fuchs and the “ghosts” of the British and US intelligence services. What emerges is primarily an account of the British domestic counter-intelligence agency’s interactions with Fuchs, something at times closer to what James Angleton, long-serving chief of the CIA’s counterintelligence staff, called a drugstore thriller rather than a historical study.

Close dwells on the thoughts and actions of intelligence agents, such as William Skardon, Kim Philby and Robert Lamphere – but tells us little about Fuchs’s colleagues and, to some extent, friends, such as Born, Robert Oppenheimer and Teller. As MI5 appears to have been unaware of Fuchs’s significance, apart from his espionage activities, it would be natural for that secret intelligence agency’s narrative to concentrate on its own actions, which Close describes, sometimes hour by hour. This unfortunately is at the cost of what Close is particularly well suited to inform his readers about, as his professional expertise is in the same field as that of Fuchs and as he was Fuchs’s successor, a few times removed, as head of Theoretical Physics at the British atomic energy research establishment, Harwell.

In largely following MI5’s interests, and lack of them, Close tells us little about Fuchs’s prewar research on the conductivity of thin metallic films, cited 2,500 times, often by researchers in Silicon Valley; provides only sketchy accounts of his work and significance in the Manhattan Project and at Harwell; says nothing about the nine years Fuchs spent in prison, and nothing about the quarter of a century of his later work in Germany. Even the careers and roles of the major figures of communist espionage in Britain – Jürgen Kuczynski, Simon Kremer and Ursula (“Sonya”) Kuczynski – are dealt with in such a cursory manner as to be misleading. In this, too, he follows MI5’s interests, and lack of them. Close repeatedly goes out of his way to state that Fuchs was not in the first rank – not as significant a theorist as Fermi, Bohr, Einstein – only to assert as frequently that Fuchs was “the grandfather” of the hydrogen bomb, essential to the successful completion of the Manhattan Project, central to Britain’s postwar atomic energy programme.

The interest of Fuchs for the non-scientist is that he decided sometime in 1941 to provide the Soviet Union with information about the British Tube Alloys atomic bomb research and from 1944 that of the Manhattan Project. Fuchs said that he did this in order to prevent any one country from having a monopoly of nuclear weapons and in this way to prevent a nuclear third world war. In this he was successful. There were ethical, political and legal implications to his actions. Ethically, Fuchs followed his father’s radical Protestant and Quaker teaching that one should always do what one believes right, without regard to convention. But it was unforgivable for many that he had violated the trust of a country that had given him refuge. Politically, the central issue of the status of information about the atom bomb and nuclear power was highly contentious. The American government, and, especially, Congress and the military, were adamant that “the secret” of the atom bomb was American property, bought and paid for, and would not, could not, be revealed to others. Hence the execution of the Rosenbergs. The British government disagreed, in some moods only to the extent of claiming a right to be in on the secret, in others arguing for international control. Many in the scientific community came down on the side of international control or simply refused to participate. The Nobel laureate Harold Urey refused to work on the project; Joseph Rotbat left Los Alamos when it became apparent that Germany was not going to produce an atomic bomb (and after hearing General Groves state that the bomb was being developed to be used on the Soviet Union). Key members of the British team at Los Alamos withdrew to universities after coming home. Oppenheimer, Einstein, Bohr and others were involved in efforts to bring about international control of the bomb after the Second World War.

The legal question was at one level fairly cut and dried. Once Fuchs confessed to providing information to a foreign government (violating the Official Secrets Act), and was brought to trial, his conviction and subsequent imprisonment were not in doubt. It seems that Fuchs agreed, even when he thought that the punishment would be execution. However, as Close explains, there were questions about whether his confession had been induced by promises of an outcome involving a transfer from Harwell to the University of Liverpool, and about lack of counsel during questioning, and so forth. More importantly, there was the legal-political question of co-ordination between MI5, the judiciary and the government. Fuchs’s question at his arrest – “Do you know what this means for Harwell?” – referred to his central role in the British nuclear programme (atomic bombs, nuclear reactors, hydrogen bombs) all of which were arguably significantly delayed by his removal from the scene. Did the Attlee government allow Fuchs’s arrest, given the opportunity to intervene, or was there so much pressure from the United States that it allowed it, even against Britain’s own interests? Close, focused on the minutiae of wire taps and car chases, skates over these issues.

For a thoughtful, well-rounded account of the career of Klaus Fuchs, there is the biography by the journalist Mike Rossiter, The Spy Who Changed the World: Klaus Fuchs and the secrets of the nuclear bomb (2014). Frank Close has given us a shorter summary of that career and an extensive, up-to-date, account of MI5’s actions and opinions: what one might call the policeman’s view.

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