Graham Farmelo’s review of a new book by Frank Close about the atom spy Klaus Fuchs (Review, 17 August) fails completely to understand the motivation of Fuchs or comprehend the historical context of his action. He simplistically labels him the “most cunning of traitors”.

Fuchs came from a deeply religious family. He was the son of a Lutheran pastor who became a Quaker after the Lutheran church began collaborating with the Hitler regime. His whole family was persecuted by the Nazis.

His father, brother and sister were incarcerated for speaking out against the regime. His sister and his communist brother-in-law helped organise the escape of Jews and other opponents of the Hitler regime from Germany. Both his mother and sister would kill themselves as a result of Nazi persecution. Fuchs himself joined the Communist party because he felt that the communists were the only ones to effectively oppose the Nazis. As a brilliant physicist he worked on the Manhattan Project, fearing like many of his colleagues that if they did not do so then Hitler would get there first. Once he became aware that Britain and the US were not going to share the new knowhow with the Soviet Union, he was concerned that they might use the bomb against them once Hitler had been defeated.

Fuchs felt that if the Soviet Union had the wherewithal to make its own bomb, this would prevent its misuse by one nation alone. One can deprecate his clandestine leaking of this information to what was at the time an ally, but he was hardly a traitor in the usual sense of the word. He was deeply opposed to war and acted on his conscience. Fuchs should be viewed more as a victim of burgeoning cold war politics than as someone who “betrayed … the country that had welcomed him as a refugee from nazism”.

John Green

London

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