end, and as was true for the Russians, the American restrictions may not have been decisive, for the British had already determined to move ahead with a nuclear weapons program. Less than two weeks after Japan had agreed to surrender on American terms, British Prime Minister Clement Attlee, who had taken office the previous month following Churchill’s shocking repudiation at the polls, declared, in a memorandum to his advisers, that a decision regarding the atomic bomb was ‘imperative’. Already on the drawing board were plans for a plant to enrich uranium. That October, the Chiefs of Staff concluded that a weapons-building project ought to be undertaken at once; ‘to delay production’ while waiting for the Americans to make up their minds about information distribution and international control ‘might well prove fatal to the security of the British Commonwealth’. Churchill, having experienced the frustrations of negotiating Britain’s junior partner status with the Americans, chimed in from the Commons in November that ‘we should make atomic bombs’— indeed, he regarded the decision to do so as ‘already agreed’. Attlee and his Cabinet duly approved the construction of a plutonium pile in December 1945. The Foreign Secretary, Ernest Bevin, was particularly avid. Once the Americans had publicized, in spring 1946, their Baruch Plan, Bevin said: ‘Let’s forget about the Baroosh [Plan] and get on with making the fissle.’ There was a flurry of appointments in January 1946. Charles Portal, now a viscount, who had overseen Butch Harris’s strategic bombing of Germany, was named controller of production of atomic energy. Christopher Hinton, an engineer with experience building weapons’ plants, took charge of constructing a pile in Lancashire. John Cockcroft, late of successful stewardship of joint nuclear work in Canada, became the director of the Atomic Energy Research Establishment, headquartered at an old airfield called Harwell. Advising the project was Chadwick, who had worked closely with the Americans, including at Los Alamos. And William Penney, who had also been at Los Alamos and over Nagasaki, was appointed on New Year’s Day as Chief Superintendent of Armament Research, ultimately the most powerful post of all, its importance much enhanced by the quality of the scientist who filled it. The government, on 1 May, presented the Commons with an Atomic Energy Bill, preceding by three months Truman’s signature on the McMahon Bill. The secret decision, in January 1947, to move ahead with bomb building thus ratified rather than established the direction in which the British were plainly heading.
‘That autumn’, wrote C. P. Snow in The New Men, his 1954 novel about the British atomic scientists, ‘it was strange to hear the scientists alone, trying to examine their consciences, and then round a committee table.’ ‘ “I don’t think we’ve got any options,” says one of them. “Luke’s [Penney’s?] right, the Barford [Harwell?] boys are right, we’ve got to make the infernal thing.” ’ Attlee would explain the British decision as ‘essential’. ‘We couldn’t allow ourselves to be wholly in their hands,’ he said of the Americans. Britain ‘could not agree that only America should have atomic energy’. Bevin concurred: ‘We could not afford to acquiesce in an American monopoly of this new development.’ Neither man was explicit about building a bomb, but that is what they meant to do. The decision to go for a weapon, as Margaret Gowing has summarized it, was not ‘a response to an immediate military threat but rather something fundamentalist and almost instinctive—a feeling that Britain must possess so climacteric a weapon in order to deter an atomically armed enemy, a feeling that Britain as a great power must acquire all major new weapons, a feeling that atomic weapons were a manifestation of the scientific and technological superiority on which Britain’s strength, so deficient if measured in sheer numbers of men, must depend’. Whether any of these desires, ‘instinctive’ as they were, could have been satisfied by American willingness to collaborate fully