The Last Man Who Knew Everything

by David N. Schwartz

  Two addenda accompanied the main report. One was written by Harvard president Conant and signed by seven of the nine GAC members. They argued that such a weapon should never be built; that it was far from certain that such a weapon would be technically feasible; that if the Russians were to develop such a weapon our atomic arsenal would provide an adequate deterrent; and that the United States had an opportunity to provide “by example some limitations on the totality of war.” Having let the nuclear genie out of the bottle, these scientists now had second thoughts and were looking for ways to persuade him to return.

  Rabi and Fermi offered a far more forceful “minority report,” which focused explicitly on the moral component of the question. It was an extraordinary statement, probably drafted by Rabi, but with Fermi’s collaboration. Rabi had long supported aggressive efforts to find a way to establish international control over these weapons and their fundamental technology, and Fermi was sympathetic to such an objective, although probably more skeptical than Rabi of its potential for success. For Fermi, opposition to moving ahead with a program for the hydrogen bomb may have reflected the same inner conflicts he experienced periodically during the Manhattan Project. The two friends began their report with the observation that the Super would only provide an advantage over conventional nuclear weapons if the destructive force were a hundred to a thousand times that of “ordinary atomic bombs,” which could destroy some 150 to 1,000 square miles of territory. Such a weapon, they argued, went far beyond any military applications; indeed, it approached the level of great natural catastrophes. “It is clear that the use of such a weapon cannot be justified on any ethical ground which gives a human being certain individuality and dignity even if he happens to be a resident of an enemy country.” Such use would place the United States in a questionable moral position in the eyes of “the peoples of the world.” The radiation released by these weapons would make large areas of the planet uninhabitable for “a very long time.”

  The two scientists ended their minority report with a call to invite other nations to join the United States in the pledge:

  The fact that no limits exist to the destructiveness of this weapon makes its very existence and the knowledge of its construction a danger to humanity as a whole. It is necessarily an evil thing considered in any light. For these reasons, we believe it important for the President of the United States to tell the American people and the world that we think it is wrong on fundamental ethical principles to initiate the development of such a weapon.

  The GAC report with addenda went to the AEC for consideration. After much debate, the commission voted to support the specific policy recommendations of the GAC, with predictable responses from Lawrence and Teller, both of whom frantically opposed ending work on the Super. Other physicists lined up on either side of the debate. For example, Leona Libby confronted Fermi sharply when she learned of his opposition and reports that, uncharacteristically, he responded with a volcanic outburst, defending himself against her attack. Debate within the scientific community raged over the next few months, but once again, as in the decision to use the atomic bomb against Japanese targets, President Truman paid little attention to the scientists. He believed, as did several members of the AEC itself, including most notably future AEC chairman Lewis Strauss, the United States should develop the weapons before the Russians did and more broadly had little faith in efforts to exert international control over nuclear weapons. The president also had to deal with the political fallout of the January 1950 revelation that Klaus Fuchs had been spying for the Soviet Union since the beginning of the Manhattan Project. Weighing both political and military considerations, President Truman rejected the AEC’s advice and ordered a high-priority effort to develop the hydrogen bomb.

  Truman’s directive notwithstanding, the scientific obstacles to actually developing the fusion weapon continued to challenge scientists. During the summer of 1950, Fermi returned to Los Alamos and continued working on how to solve this major technical puzzle. He brought Richard Garwin with him and they worked closely that summer.

  Fermi often expressed skepticism about the practicality of Teller’s concept. By the summer of 1950 he was still a skeptic, as was Ulam. They both worried that with Teller’s design, the hydrogen fuel would only partially fuse before the reaction burned out. The calculations to determine the nature of this problem were complex, and Fermi and Ulam decided on a good-natured race to see who could come up with the answer first. Fermi wanted to use slide rules only, but Ulam’s technical department insisted on using the services of a group of young women “computers” using mechanical calculators. Ulam and Fermi did some preliminary calculations to set up a spreadsheet for the women to complete and the women came back with the results, which the scientists incorporated and used to direct additional rounds of calculations. One particularly attractive and buxom young woman, Miriam Planck (no relation to the quantum pioneer Max Planck), spent a fair amount of time with Fermi, which Ulam and John Wheeler both noted with amusement.*

  Throughout the summer, Ulam and Fermi, and others, notably a physicist named C. J. Everett, repeatedly pointed out fatal flaws in Teller’s Super concept. Teller would return time and again with ideas to overcome the concept’s deficiencies, but each time someone would find a new fatal flaw. It took a flash of insight by Ulam in early 1951, who realized that compressing the entire fusion assembly during the fission trigger would create enough pressure to hold the configuration together just long enough for the device to work. Teller’s contribution was to think of reflecting the high-energy X-rays emanating from the fission trigger to create that compression. Ulam and Teller worked out the main details of this solution in a paper written in March 1951. By November 1952, the Ivy Mike test, conducted on the South Pacific island of Eniwetok, confirmed the feasibility of a fusion weapon based on the Teller-Ulam concept.

  That Fermi continued to work on the project after having helped to draft such a strong statement against the weapon’s development is perhaps the single most puzzling aspect of his postwar public service. He spent the summer of 1950 at Los Alamos, immersed in the fusion project along with many old friends such as Ulam, Teller, Wheeler, and Bethe. Bethe, too, was initially opposed but came on board after the Korean War broke out in June 1950. It remains a mystery what drew Fermi to join the project when eight months before he labeled this weapon “necessarily an evil thing considered in any light.”

  Fermi never wrote about his decision to participate. Perhaps he wanted to be viewed as a patriot and, given the president’s decision on behalf of the country to move ahead, he felt working on the project was his duty. The physics issues were as compelling as they had been at Los Alamos six years previously. This may well have added to the allure of working on the fusion weapon. Perhaps because the project was going ahead anyway, Fermi felt he should participate from inside rather than look in from the outside. On the inside, he could continue to play the role of the “pope who plays the devil’s advocate,” a role we know he enjoyed.

  On the surface it is surprising that Fermi did not come up with the Ulam-Teller idea first, because in retrospect it seems so obvious and should have been to someone of Fermi’s enormous intellect. Both Fermi and Garwin worked extensively on X-ray pressure issues during that summer, yet neither of them thought of using that pressure to keep the assembly together for the required amount of time. It fell to Ulam to come up with the original insight of compression and to Teller to extend the compression to X-ray pressure. Fermi’s reasons for participating remain a mystery to this day. In the end, he was not the one who invented the hydrogen bomb.

  When Fermi’s four-year term on the GAC was up, in early 1951, Oppenheimer asked him to stay on. Fermi gave a number of reasons for refusing but ended by saying that he had come to distrust his own judgment. The timing, of course, was bad. The Chicago cyclotron was about to go live and over the previous five years he had been planning a number of important experiments that would now take priority. One also senses that
this expression of distrust in his own judgment was not false modesty, that important public policy debates made him deeply uncomfortable. The further away discussion veered from physics itself, the more he felt that he had little of value to contribute, especially because within his own field of expertise he had so very much to contribute and had the confidence in his ability to make a difference. Public policy issues were, in the end, governed not by equations on a page or experimental results one could publish in journals but rather by an uneasy combination of technical fact and value-based opinion. When Fermi friends like Teller and Rabi could disagree among themselves so vehemently, there were manifestly no “correct” answers. Fermi must have felt himself at sea. From this point onward he would do what he could to avoid public policy debates and stick to his physics, with only partial success.

  IN 1952, PUBLIC POLICY ISSUES AGAIN APPEARED ON FERMI’S RADAR screen, when he received a letter from New York attorney Emanuel Bloch, who was representing the most notorious couple in the United States at the time, Julius and Ethel Rosenberg. Charged with providing atomic secrets to the Soviet Union, they had been convicted more than a year earlier and now Bloch was desperate to find some way to spare them from the death penalty imposed at sentencing. He wrote to Fermi asking him to opine on whether certain information was generally available in the public domain.

  Fermi clearly wanted nothing to do with the case. He referred Bloch to Gabriello Giannini, his former student who, in his current role as the manager of the patent litigation proceeding on behalf of the Via Panisperna boys, would be in a better position than anyone to determine what knowledge was in the public domain and what was not. It was just about this time that many of the patents Fermi and Szilard had applied for were coming up for declassification review. Perhaps Fermi hoped that Giannini might know of information that would serve to lessen the severity of the sentence. Fermi himself chose to be of no direct help and, when Bloch wrote again in late 1952 asking for intervention on behalf of his clients, the letter appears to have gone unanswered. Fermi must have found this correspondence upsetting. He firmly believed that no scientific discoveries could remain secret forever, and so probably viewed Soviet acquisition of nuclear weapons as a foregone conclusion, especially given the considerable talents of Soviet physicists. Nevertheless he was intensely loyal to the country he now called home and must have despised the idea of a native-born couple who could betray their nation.

  IN 1947 KARL DARROW, THE SECRETARY OF THE AMERICAN PHYSICAL Society (APS), the main professional organization of physicists in the country, invited Fermi to be nominated as vice president of the APS. The vice president position was a relatively undemanding role, typically given to someone who would agree, after a year, to become president of the APS. Fermi politely but firmly refused, citing professional commitments that would prevent him from performing either role. He had already accepted the GAC appointment and had a full teaching and research schedule at Chicago. He clearly had no intention of distracting himself further with a largely administrative role, much less the higher profile role of president the following year.

  Darrow must have approached Fermi several times in the following years, because the message sent to Fermi in 1951 was more than a bit aggressive. When Fermi tried to decline, Darrow informed him that he was the nominating committee’s only choice, that there was no way within the constitution of the organization to take him off the ballot, and that Darrow “dared to hope that you [Fermi] will not wish to join the Italian gentleman that Dante placed in the Inferno because he made ‘Il gran rifiuto’ [the Grand Refusal].” Under such intense pressure, Fermi reluctantly agreed to serve as vice president for the 1952 term and in 1953 gracefully became president. Fermi made sure that his old friend Hans Bethe came along for the ride as vice president, positioning him to take the reins in 1954. Bethe had been a friend from the early days, and the two had worked closely together at Los Alamos. Bethe also had a reputation as an easygoing, likeable personality with the scientific gravitas to step into Fermi’s shoes when Fermi’s term was over.

  Fermi’s vice presidency was uneventful and distracted him little from his experiments at Chicago. However, his tenure as president was an entirely different matter. Almost at once he found himself embroiled in a purely political controversy that, almost seventy years later, seems faintly ludicrous but that, at the time, preoccupied Fermi, the APS, and the physics community in general for several months.

  Allen Astin, the director of the National Bureau of Standards (NBS), was suspended by the Secretary of Commerce to whom he reported, because the bureau had informed the US Postal Service that a certain battery additive did not measure up to the claims of its manufacturers, thus making it impossible for the company to use the US mail to distribute the product. The new Secretary of Commerce, a Republican businessman and politician named Sinclair Weeks, declaring that the marketplace should be free to decide these matters, directed the postmaster general to ship the offending battery additive, and summarily suspended Dr. Astin for his temerity. Legitimately fearing the chilling effect that such an action would have on advice given to government agencies, the APS, under Fermi’s leadership, issued a strong statement in support of Dr. Astin’s scientific integrity, urging the government to adopt policies designed to maintain the independence and integrity of scientific advice. In August 1953, Secretary Weeks reversed Dr. Astin’s suspension but directed the postmaster general to lift the ban on shipping the product. No one at the APS was particularly satisfied with the outcome, but the organization could say with some satisfaction that it had defended one of its own.

  Perhaps of greater significance in retrospect was a little-known controversy that Fermi presided over in relation to the summer 1953 meeting of the APS, scheduled to take place at Duke University in Durham, North Carolina. During the planning for the meeting, APS Secretary Darrow pointed out to Fermi that the hotels in Durham were segregated. Though some accepted African American guests, some were “whites only.” There were very few African American members of the APS, but the question nevertheless arose: Should the APS take some sort of stand on the matter? When Fermi was apprised of the situation, he was upset. His preference was for the APS to send out a full list of hotels in Durham, not indicating which ones were segregated. Perhaps he believed that African American members of the APS armed with full knowledge of the situation would force a showdown with “whites only” hotels. Others on the APS executive committee disagreed and pressed for a letter from Secretary Darrow to all African American members providing a list of Durham hotels that would welcome them so as to avoid confrontation. Ultimately, the executive committee prevailed over Fermi’s wishes and the list of hotels that would welcome African American guests was sent to all members.

  His problems were not yet over. In late 1953, the AEC electrified the physics world with the announcement that it would review J. Robert Oppenheimer’s security clearances in light of suspicion that he might have been a Soviet spy during the Manhattan Project.

  THE OPPENHEIMER CASE WAS NOT THE FIRST TIME THE LOYALTY OF US government scientists had come under scrutiny. In 1949–1950, the University of California required all professors to sign an anti-communist “loyalty oath.” Highly controversial and divisive, the requirement affected professors and staff across all disciplines. Jack Steinberger, who was at Berkeley at the time, had not hidden his left-leaning political orientation and refused to sign the oath. Steinberger had never gotten along with Luis Alvarez, a major figure at Berkeley and a fairly conservative Republican, and his refusal only made things worse. In the end, Steinberger was forced to leave Berkeley and moved to Columbia. Considering that Steinberger would go on to do Nobel Prize–winning work at Columbia, this was clearly Columbia’s gain.

  In one of the few comments we have from Fermi on political issues during this period, he wrote a letter to his former student Geoffrey Chew in which he comments on the Berkeley situation. Fermi’s attitude in the letter is surprising only if one fails to consider that
he signed an oath of loyalty to the Fascist Party as a requirement for retaining his professorship in Rome. Fermi indicated to Chew that he didn’t understand what the fuss was about, because the Berkeley oath had been so “watered down” as to be, in Fermi’s mind, essentially meaningless. Clearly, Fermi would have signed and was fairly relaxed about such oaths if they were the price to be paid for freedom in the lab.

  Fermi was also aware of the case of Edward Condon, the director of the National Bureau of Standards in 1948, who came under fire from House Un-American Activities Committee (HUAC) chairman J. Parnell Thomas for supposed ties to the Soviet Union. The charges were baseless and the APS came to Condon’s defense. President Truman used the opportunity to show his defiance of the HUAC’s agenda and publicly endorsed Condon. Eventually, the case lost momentum, although the HUAC occasionally resurfaced the charges, with little substantive effect.

  The Berkeley loyalty oath controversy and the Condon case were both high profile, but the case against Oppenheimer was in a different league altogether. Americans were astonished that the charismatic leader of the Manhattan Project could be suspected of disloyalty to the US government. It would become a defining moment in the relationship of science and government and an iconic drama in American Cold War politics.