by Ray Monk
Puzzled by the mention of three scientists, but sure now that the FBI must somehow have received information about his conversation with Eltenton and his abortive attempt to approach Oppenheimer on Eltenton’s behalf, Chevalier told the agents the story, such as it was, of his extremely brief and unsuccessful experience of acting on behalf of Soviet intelligence. At the same time, in Oakland, Eltenton told roughly the same story: after being approached by Peter Ivanov from the Soviet consulate, he had asked Chevalier to ask Oppenheimer if he would be willing to pass information to the Soviets. A few days later, Eltenton said, Chevalier ‘dropped by my house and told me that there was no chance whatsoever of obtaining any data and Dr Oppenheimer did not approve’. No matter how many times they were asked, no matter how much pressure was put on them, neither Chevalier nor Eltenton said anything that provided any support to the idea that three scientists had been approached. Indeed, Chevalier put his claim in writing: ‘I approached no one except Oppenheimer to request information concerning the work of the radiation laboratory.’
Despite all their strenuous – indeed, obsessive – attempts to prove Oppenheimer’s complicity in a major espionage effort, all the FBI had to show for hours of interviewing and days of surveillance was evidence of a momentary, clumsy exchange between Oppenheimer and Chevalier, in which Oppenheimer refused to provide information. Why, despite the lack of any kind of evidence, was the FBI so convinced that Oppenheimer must be in league with the Soviet Union? The answer seems to be that they were unable, otherwise, to account for his post-war political views. On the other hand, Chevalier, on his return to Berkeley in the summer of 1946, was shocked to discover how far Oppenheimer’s political views had shifted to the right and how anti-Soviet he had become. ‘I cannot tell you why,’ Oppenheimer told Chevalier, ‘but I assure you I have real reason to change my mind about Russia. They are not what you believe them to be.’
This is not how it seemed to the FBI. They had no direct evidence that he was pro-Russian (despite looking very hard to find some), but there were two aspects to his post-war political attitudes that they found hard to explain without attributing to him a desire to help the Soviet Union. The first was his, to their minds, otherwise unfathomable advice to the US to give up its monopoly of atomic weapons, share information with the Soviets and cooperate with them on the development and control of atomic energy. The second was his apparently fervent conviction that no more atom bombs should be built and his opposition to any further atomic bomb tests.
When he was asked what should become of Los Alamos after the war, Oppenheimer replied: ‘Give it back to the Indians.’ Of course, such a plan was never even considered. Instead, though employing far fewer people, it continued to exist after the war as both a research establishment and as an atomic-bomb production facility, with Norris Bradbury replacing Oppenheimer as director. Its first post-war task was to produce further ‘Fat Man’-type bombs, some of which would be stockpiled and others set aside for a series of tests that was planned to take place in the summer of 1946.
These tests, code-named ‘Operation Crossroads’, were first devised at the end of 1945 as a means of investigating the effect of an atomic bomb on a naval fleet. The idea was to assemble a fleet of obsolete and captured ships, some German and some Japanese, and then attempt to destroy them in various ways using atomic bombs. Three such tests were planned. In the first, named Able, a B-29 was to drop a bomb over the fleet; in the second, Baker, a bomb was to be exploded just below the surface of the sea, attacking the fleet from below; while in the third, Charlie, a bomb was to be exploded half a mile under the ships. The place chosen for the tests was Bikini Atoll, in the middle of the Pacific Ocean. Unlike the Trinity test, these were not to be secret, but rather extremely public, with the media and observers from all over the world, including Russia, invited to witness what was expected (and no doubt hoped) to be a shocking spectacle.
Adding further to both President Truman’s dislike of him and the FBI’s suspicion of him, Oppenheimer wanted nothing to do with Operation Crossroads. The tests were originally scheduled for May 1946, but, at the request of Secretary Byrnes (who did not want them to influence the negotiations over international control of atomic energy), were postponed until July. On 3 May, responding to a request that he attend the tests and contribute to the analysis of the results gained from them, Oppenheimer wrote to Truman asking to be excluded from the scientific panel associated with the tests. Like many other scientists, Oppenheimer told Truman, he had misgivings about their scientific value and whether they could possibly reveal anything that was not already known. After all, on the basis of what had already been witnessed at Trinity, Hiroshima and Nagasaki, it could safely be predicted that: ‘If an atomic bomb comes close enough to a ship, even a capital one, it will sink it.’ And if the point was to investigate the effects of radiation, this could be done much more cheaply and more effectively in the laboratory. But, over and above those considerations, Oppenheimer raised doubts about ‘the appropriateness of a purely military test of atomic weapons’ at a time when ‘our plans for effectively eliminating them from national armaments are in their earliest beginnings’. In other words, for Oppenheimer it seemed at best pointless and at worst dangerous for the US to be testing bombs at the very time when it was (or anyway, in Oppenheimer’s view, ought to have been) trying to convince the world to adopt a plan designed to ensure that no further bombs were made or used. The point was lost on Truman, who forwarded Oppenheimer’s letter to Acheson, adding a short note dismissing Oppenheimer as the ‘cry-baby scientist’, who had come to the White House six months earlier.
Oppenheimer’s opposition to the tests became known to the press, by whom he was perfectly prepared to be quoted on the subject. On 11 June, the San Francisco office of the FBI sent Hoover a transcript of a phone conversation between Oppenheimer and a journalist for the New York Herald Tribune called Steve White. The pair discussed the forthcoming Bikini test, Oppenheimer confirming it as his view that there was no need for a test to determine that any ship within a certain radius of an atomic bomb would be destroyed. The conversation continued:
White: I also have another quotation here but I haven’t got your name on it.
Oppenheimer: What’s that?
White: If the bomb fails entirely, it will likely prove something. It will prove that you can’t do these things without good people.
Oppenheimer: OK. That shouldn’t have my name on.
Many of the misgivings that Oppenheimer expressed to Truman and to the press were expressed persuasively in an anonymous article published in the 15 February 1946 edition of the Bulletin of the Atomic Scientists of Chicago, a journal that had only been in existence for two months, but was already recognised as the voice of the politically concerned scientists of the Manhattan Project. In addition to the points made by Oppenheimer in his conversation with White, the Bulletin article also made the telling, and, as it turned out, prescient observation:
Naval vessels are mechanically stronger than buildings, so that over comparable distances, the effect of a bomb on a warship would be less than on a building. Most of the ships will be several miles away from the explosion, so that they will probably remain afloat. Those who have been led to expect the overwhelming destruction of the fleet will thus be disappointed and public opinion may be lulled into a feeling of false security – along the line of ‘Oh, the atomic bomb is not so terrible – it’s just another big bomb.’
In fact, this is just what happened at the first test, Able, which took place on 1 July 1946, in front of an audience of more than a hundred people, including two observers from the Soviet Union. The fleet to be destroyed consisted of twenty-three ships, the central target of which was the battleship USS Nevada. Of these, only two were sunk by the initial blast (within twenty-four hours, a further three sank); the Nevada remained afloat. ‘Dressed in all the trappings of an exaggerated and sometimes frivolous publicity,’ The Economist reported, ‘the first Bikini atom bomb experimen
t has left rather the impression of a fireworks display which slightly misfired.’ One of the Soviet observers remarked that the damage inflicted by the bomb was ‘not so much’. In fact, the blast, measured at 23,000 tons of TNT, was as powerful as any bomb that had yet been exploded, and the test did provide incontrovertible evidence of the devastating effect of radiation. On board the ships were hundreds of mice, rats, goats and pigs, the death rate of which was enough to suggest that, though the Nevada remained afloat, had it been fully manned, it would, within a few days have been, a ‘ghost ship’, a floating coffin for a crew whose every member would have died.
The second test, Baker, took place on 25 July and provided a much more arresting display. A ‘Fat Man’ bomb was suspended beneath a landing craft and detonated just ninety feet underwater. The result was spectacular indeed: the landing craft was vaporised and a huge vertical column of water and steam was created, which destroyed ten ships. By this time, however, there was little public interest in, and much criticism of, the tests. The Soviet reaction was expressed in a Pravda editorial that described the tests as ‘common blackmail’, which ‘fundamentally undermined the belief in the seriousness of American talk about atomic disarmament’. The third test, Charlie, was called off.
The day before the Baker test, Lilienthal recorded in his diary a meeting with Oppenheimer in his hotel room in Washington. Oppenheimer, he wrote, ‘is in deep despair about the way things are going in the negotiations in New York’.
It is difficult to record how profoundly hopeless he thinks it is; indeed, when I said that there are some situations in which one cannot acknowledge despair, he took me to task for this, in a gentle but firm way, saying that it was this sense of a ‘reservoir of hope’ that was quite wrong, for it does not exist.
If the Baruch Plan failed, Oppenheimer told Lilienthal, it:
will be construed by us as a demonstration of Russia’s warlike intentions. And this will fit perfectly into the plans of that growing number who want to put the country on a war footing, first psychologically, then actually. The Army directing the country’s research; Red-baiting; treating all labor organizations, CIO first, as Communist and therefore traitorous etc.
Lilienthal recorded that Oppenheimer ‘paced up and down in the frenetic way’, saying all this ‘in a really heart-breaking tone’.
He is really a tragic figure; with all his great attractiveness, brilliance of mind. As I left him he looked so sad: ‘I am ready to go anywhere and do anything, but I am bankrupt of further ideas. And I find that physics and the teaching of physics, which is my life, now seems irrelevant.’ It was this last that really wrung my heart.
Oppenheimer did in fact, during that summer, make some moves towards returning to physics. He finally agreed, for example, to return to his old arrangement of lecturing at Berkeley for half the year and Caltech for the other half, beginning that autumn. After his experiences at Los Alamos and, during the year following the war, his experience of being part of US policy-making at the very top of the political process, he no doubt knew that he could not simply return to his pre-war life. Nevertheless, there are signs that at least part of him wanted just that. Even during the war, despite his quip to Pauli that ‘for the last four years I have had only classified thoughts’, he had managed to publish at least one article on theoretical physics. Admittedly the article in question – ‘Cosmic Rays: Report of Recent Progress, 1936–1941’, published in a collection commemorating the seventy-fifth anniversary of the University of California – was synoptic and introductory, rather than an original contribution to research. Nevertheless, it gives some indication of what Oppenheimer was hoping to return to when the war was over. In a section on ‘Mesons and Nuclei’ Oppenheimer discusses the puzzles that arise from the enigmatic Yukawa particle, to which he had devoted so much of his energy during the 1930s. The existence of this particle – named the ‘meson’ because its mass put it somewhere in the middle between the tiny electron and the comparatively huge proton – was postulated by Yukawa in order to explain nuclear forces, and, it was thought, was observed in cosmic rays. The troubles arose from the fact that the properties of the particle detectable in cosmic rays were not consistent with it being the particle postulated by Yukawa. ‘The situation in this respect,’ Oppenheimer writes, ‘is not only rather complicated; it is also very incompletely understood, and presents at the moment the principal challenge to theoretical physics.’
It was this ‘principal challenge’ to which Oppenheimer wanted to devote himself. Astonishingly, even right in the middle of the UN negotiations over international atomic-energy policy, he had managed to pursue original research into an aspect of this challenge. On 26 June 1946, the Physical Review received a paper jointly written by Oppenheimer and Hans Bethe entitled ‘Reaction of Radiation on Electron Scattering and Heitler’s Theory of Radiation Damping’. This was a response to work published in 1941 and 1942 by the German Jewish physicist Walter Heitler, who, after escaping Hitler’s Germany, had worked first at Bristol with Nevill Mott and then at Dublin with Erwin Schrödinger. At Dublin, Heitler collaborated with the Chinese physicist Peng Huanwu on a mathematical theory that, they hoped, would contribute to the understanding of cosmic rays, mesons and quantum electrodynamics. The paper by Oppenheimer and Bethe (which, at eight pages, was by Oppenheimer’s standards fairly long) was a reaction to the Heitler–Peng paper, ‘The Influence of Radiation Damping on the Scattering of Mesons’, which had been published in the Proceedings of the Cambridge Philosophical Society in 1942. What Oppenheimer and Bethe showed was that the equations devised by Heitler and Peng had only limited success in describing the scattering of electrons by electromagnetic energy. As an attempt to meet the ‘principal challenge’, this paper with Bethe was small beer, but, given what else Oppenheimer was doing in the summer of 1946, its very existence is something of a marvel.
On returning to California that summer after his work on the Baruch Plan, Oppenheimer narrowly missed what might have become an opportunity to build on the extraordinary work on astrophysics that he had done immediately before the war, the work now regarded as his most important contribution to science. Waiting for him on his return to Berkeley was a letter, dated 15 July 1946, from the Harvard astronomer Donald Menzel, whom Oppenheimer had known in the 1920s and ’30s, when Menzel was working at the Lick Observatory in California. What Menzel wanted was to arouse Oppenheimer’s interest in some speculations he had regarding the structure of the sun. His suggestion, prompted in part by Bethe’s seminal work on solar structure, was that the sun should be regarded as an enormous atom, with most of its mass concentrated in an extremely dense ‘nucleus’. ‘I think that this problem is important from the physical standpoint,’ Menzel told Oppenheimer, ‘because it may be tied up with the generation of cosmic rays.’ Next time Oppenheimer was in the east, he suggested, perhaps the two of them could meet in New York, Philadelphia or Washington to talk about it.
Oppenheimer’s reply, written on 8 August, was fairly encouraging. ‘I would like to talk over with you your ideas on stellar interiors,’ he told Menzel, suggesting that the forthcoming American Physical Society meeting in Princeton might provide an opportunity. ‘I may have to come East before then,’ Oppenheimer wrote, ‘but I devoutly hope not.’ Menzel, as he told Oppenheimer in a subsequent letter, was unable to attend the Princeton meeting, but was still hoping to lure Oppenheimer into further thinking on the subject. ‘There are certainly a lot of interesting and important problems in astrophysics,’ Menzel told Oppenheimer, ‘relating to atomic structure, nuclear structure, and interpretation of spectra. If only we could get together once in a while, as we used to many years ago, I am sure we could have a lot of fun.’
Even while Oppenheimer and Menzel were exchanging these letters, however, moves were afoot in Washington that would guarantee that both Oppenheimer’s devout hope not to return to the east and Menzel’s hope that he and Oppenheimer could have fun discussing astrophysics were destined to be thwarted. On 1 Au
gust, President Truman signed the McMahon Bill, bringing into law the Atomic Energy Act.
Brien McMahon had first presented his bill to Congress in December 1945 as an alternative to the defeated May–Johnson Bill. Its fundamental principle was to ensure – as the May–Johnson Bill had so conspicuously failed to – that atomic-energy policy was kept in civilian rather than military hands. Its chief means of ensuring this was through the creation of the entirely civilian Atomic Energy Commission (AEC), which would have responsibility for the development and control of both military and non-military uses of atomic energy. The man Truman chose to be the first chairman of the AEC was David Lilienthal, thus ensuring that Oppenheimer would be called back to Washington to play a key role in the shaping of US atomic-energy policy.
The Atomic Energy Commission was a five-man body, which, according to the terms of the McMahon Act, took over from the Manhattan Project on 1 January 1947. This meant, for example, that Los Alamos was now a civilian rather than a military establishment. Apart from Lilienthal, the commissioners were Sumner T. Pike, a businessman from New England; William T. Waymack, a farmer and newspaper editor from Iowa; Robert F. Bacher, the only scientist on the commission; and Lewis L. Strauss, a politically conservative banker and reserve admiral. Strauss, who insisted that his name be pronounced ‘straws’, was a former shoe salesman who had become extremely wealthy and, through acting as an aide to President Hoover, politically influential. On 24 October 1946, Oppenheimer was recorded by the FBI as remarking about Strauss: ‘He is not greatly cultivated but will not obstruct things.’
