The Pope of Physics

by Gino Segrè

  Of the four sites selected by the Target Committee, Groves favored Kyoto, but Stimson overruled him. This distinguished elder statesman, formerly secretary of war (1911–1913) and secretary of state (1929–1933), had also been governor general of the Philippines before assuming that post. During that time he had visited Kyoto and came to appreciate the significance of Japan’s ancient capital to the nation. Stimson felt that, given the city’s history, it should not be destroyed. Groves bowed to his insistence; Hiroshima was selected in its place as the number one target. The city had never been bombed, and it held an important army depot and port of embarkation in its industrial area.

  Three weeks after the test at Trinity, early in the morning of the sixth of August, a B-29 bomber piloted by Lieutenant Colonel Paul Tibbets took off from the United States airbase on Tinian, an island in the Northern Marianas. On the previous day, the name Enola Gay, the given name of Tibbets’s mother, had been painted on the fuselage below the cockpit, and Little Boy, a U-235 bomb, had been placed in the plane’s bomb bay.

  Little Boy was dropped at 8:15 a.m. on Hiroshima. The city’s terrorized population viewed with shock, horror, and disbelief the spectacle the Los Alamos physicists had seen from a safe distance three weeks earlier, a bomb equivalent to twenty kilotons of TNT. An estimated one hundred thousand people out of the city’s four hundred thousand population died as a result of the explosion.

  Three days after that, on the ninth of August, Fat Man, a plutonium bomb, fell on Nagasaki with similar results. On the fifteenth, the voice of the emperor, previously unheard by the Japanese public, was broadcast on a disc recorded the day before. He announced Japan’s surrender. An official ceremony was held aboard the battleship USS Missouri on September 2. World War II was over.

  33

  AFTERSHOCK

  I saw a bright blast, and I saw yellow and silver and orange and all sorts of colors I can’t explain. These colors came and attacked us and the ceiling beams of the wooden school along with the glass from the windowpane all shattered and blew away all at once.

  —Michiko Kodoma, age seven, Hiroshima survivor

  The general impression is one of deadness, the absolute essence of death in the sense of finality without hope of resurrection.… It is everywhere and nothing has escaped its touch. In most ruined cities you can bury the dead, clean up the rubble, rebuild the houses and have a living city again. One feels that it is not so here.

  —Navy Captain William C. Bryson at Nagasaki, five weeks after the bomb drop

  The first the general public learned about the discovery [nuclear fission] was the news of the destruction of Hiroshima by the atom bomb. A splendid achievement of science and technology had turned malign. Science became identified with death and destruction.

  —Józef Rotblat, physicist formerly at Los Alamos

  I don’t believe a word of the whole thing.

  —Werner Heisenberg, leading physicist of the German nuclear energy project

  Among those most stunned to hear about the American atomic bomb were ten of Germany’s leading physicists. Along with Heisenberg, they were incredulous when they heard the news. Presumably to prevent the Soviets from capturing them, the ten had been held by the British since early July at Farm Hall, a mansion near Cambridge. The British had placed secret microphones in the mansion’s bedrooms and gathering places. All conversations were recorded, unbeknownst to the Germans.

  Over dinner on the evening of August 6, the scientists struggled to decipher how the bomb could have been assembled and how they themselves had failed to solve the technicalities of producing one. These inquiries dominated the discussions, which were punctuated by continuing expressions of disbelief and condemnation. When one of the scientists opined that “it was dreadful of the Americans to have done it. I think it’s madness on their part,” Heisenberg had a quick rejoinder: “One can’t say that. One could equally well say ‘That’s the quickest way of ending the war.’” Otto Hahn, whose discovery of fission made the bomb possible, was devastated that his prewar research had led to so much death and suffering. Hahn’s précis that “I am thankful that we were not the first to drop the uranium bomb” was a sentiment seemingly shared by all but one of the ten.

  The myriad worldwide reactions to the dropping of the bomb ranged from welcome relief that the war was ended to denouncements of the United States, accusing it of crimes against humanity. It was not just the number of dead, approximating the firebombings of Dresden and Tokyo, but the horrendous nature of their deaths from radiation. America, whose international reputation hinged on being a decent and fair nation, was thrust into the macabre role of a Frankenstein.

  A 1945 Gallup poll conducted immediately after the bombing documented that 85 percent of Americans approved of using the new atomic weapon on Japanese cities. A 2015 survey found that 56 percent of Americans believe the use of nuclear weapons was justified. The issue continues to divide Americans, although fewer are now supportive of dropping the bomb. In the jarring light of hindsight, opposition and resentment have grown.

  The prevailing view in 1945 America was expressed by Secretary of War Stimson as “the least abhorrent choice” to reach the objective of ending the war quickly. Many accepted the argument that an invasion of Japan would have cost hundreds of thousands of American lives, but Stimson in a Harper’s Magazine article seemed to inflate that estimate to even greater numbers, “over a million casualties to American forces alone.”

  Whatever the number, U.S. troops felt spared. Plans had been ripening for a major invasion of Japan, combining army, navy, and air force troops. A young lieutenant, Paul Fussell, who later became a noted historian, had been slated to be part of the assault and remembered, “When the [atomic] bombs dropped … we all cried with relief and joy. We were going to live. We were going to grow up to adulthood after all.”

  It was reasoned that the bomb had saved not only American lives, but also those of the Japanese who would have perished if fighting continued. And the hope remained that its horrific consequences would act as a deterrent to future wars. This viewpoint was touchingly expressed by a twenty-year-old Los Alamos technician in a letter to his mother:

  Well at last you know approximately what goes on up here. This new bomb may sound inhuman but … this thing will mean peace forever, even with the cost of several thousands of Japanese civilians’ lives at the present. Let us pray that it will be unnecessary to use any more even on our enemy.

  The secret city had been outed in the most dramatic way imaginable. In President Truman’s August 6 statement announcing the bombing of Hiroshima, he divulged the magnitude of the Manhattan Project and the sites it comprised. For the first time, Laura understood the nature of Enrico’s work, why he needed to have the bodyguard Baudino, and why the family had moved to Los Alamos.

  Once peace was declared, Laura described the scene in the Atomic City as festive: “Children celebrated noisily, paraded through every single home, led by a band playing on pots and pans with lids and spoons.” Joy about the new peace overlapped with pride about the bomb, the two intricately entwined. Wives, who like Laura had been uninformed, could now talk about what they and their husbands had sacrificed and achieved. Men who had kept silent suddenly could speak about their work.

  Not everyone in Los Alamos felt celebratory. One scientist said, “It seemed rather ghoulish to celebrate the sudden death of a hundred thousand people, even if they were ‘enemies.’” Others, particularly those who had witnessed the explosion at Trinity, could imagine all too well what it must have been like to be caught unaware at Ground Zero. An unhappy and nauseated Robert Wilson, who had earlier described coming to Los Alamos as “romantic,” would not join the festivities. Feelings deepened after the news of Nagasaki’s destruction, the second use of an atom bomb. Oppenheimer was reported as being a “nervous wreck.”

  With the extensive destruction in Hiroshima and Nagasaki, not only was the secret out but its results began to stir the social consciousness of th
e wives of Los Alamos. Laura recounted how the women sobered when “among the praising voices some arose that deprecated the bomb, and words like ‘barbarism,’ ‘horror’ and ‘mass murder’ were heard from several directions.”

  In probing her own emotions, Laura did not have easy responses to such qualms. Thirty years later, she pondered the ethical dilemmas inherent in dropping the bomb:

  But above all, there were the moral questions. I knew scientists had hoped that the bomb would not be possible, but there it was and it had already killed and destroyed so much. Was war or science to be blamed? Should the scientists have stopped the work once they realized that a bomb was feasible? Could they have stopped it? Would there always be war in the future? To these kinds of questions there is no simple answer.

  One woman who had a decisive reaction was Fermi’s older sister, Maria, who wrote a troubled letter to Enrico from abroad. After saying that everybody in Italy was talking about the recent events, she added, “All however are perplexed and appalled by its dreadful effects, and with time the bewilderment increases rather than decreases. For my part, I recommend you to God, Who alone can judge you morally.”

  Franco Rasetti, Fermi’s best friend during university days at Pisa, expressed himself more harshly in a letter to Fermi’s early childhood friend Enrico Persico. In April 1946 Rasetti wrote, “It seems almost impossible that people that I once regarded as endowed with a sense of human dignity have lent themselves to be the instrument of such monstrous degeneration. And yet this is so and they don’t even seem aware of it … In my opinion these scientists, among them many friends of mine, including Fermi, might face severe judgment by history.”

  Rasetti never voiced this sentiment publicly, but one cannot help thinking it caused a schism between him and Fermi. Admittedly, their interests had diverged, but the two made little effort to see each other even after Rasetti moved in 1947 to a professorship at Johns Hopkins. Rasetti’s mind-set was steadfast: science cannot allow itself to be co-opted for warfare, no matter how dire the circumstances. And Rasetti had been consistent. In 1943 the British physicists working in Canada on atomic bomb development asked him if he would join them. He declined and, as he wrote in that same 1946 letter to Persico, “There are few decisions I have taken in my life for which I have had less cause for regret.”

  Although knowledge about the bomb was in Rasetti’s lexicon, it drew a blank for the vast majority of the American public prior to Hiroshima and Nagasaki. What was this new weapon, the atom bomb? Where had it been developed, who had built it, what was it made of, and were there other bombs like it?

  With remarkable foresight, Groves had anticipated that Americans would want answers to these and other questions. He commissioned in 1944 a short history of the Manhattan Project that would also explain key scientific notions to the public. Composed in total secrecy and approved by scientists and censors, the report was eerily scheduled to be ready for release by August 1945. The lead author, Henry de Wolf Smyth, was a Princeton University physicist who had worked for the project and been an associate director of the Met Lab; Groves had assured him of complete access to Los Alamos, Oak Ridge, and Hanford. With President Truman’s final approval, the report was made available on August 12, serendipitously three days after Fat Man was dropped on Nagasaki.

  The Smyth report provided a background description of the laboratories, a summary of the basics of nuclear fission and chain reactions, and a brief history of what had transpired. To the great displeasure of scientists advocating open international exchanges now that the war was over, the government also erected barriers to information sharing. One of the reasons Groves had urged writing the report was his desire for controlling intelligence flow regarding the Manhattan Project. He made this abundantly clear in a foreword, underscoring that any scientific information beyond the report’s contents would be in violation of “the needs of national security” and that anyone disclosing anything further without authorization would be “subject to severe penalties under the Espionage Act.”

  To everyone’s astonishment, the Smyth report became a New York Times bestseller, remaining on the list for many months. It was read by many, including Laura, who was given a copy by Enrico, telling her it encompassed all he could say about the work of the past years. Laura, judging herself “stupid” for not having guessed, recalled when Emilio Segrè during a 1943 Chicago visit had caustically greeted her with “Don’t be afraid of becoming a widow. If Enrico blows up, you’ll blow up too.” Other hints had been subtler.

  The Manhattan Project scientists were astonished by the wide public interest in the project and the eagerness to understand what unleashing the power of the nucleus meant for the world. Again, Fermi was pushed to the fore, asked to become a spokesperson for the report with the other three members of the Scientific Panel. It was a role he neither relished nor sought.

  In the meantime, not content to have the panel be the only voice heard in Washington, the Los Alamos scientific community began to mobilize. In spite of their isolation on the mesa and the secrecy of their mission, the scientists had not abstained from discussing among themselves the multitudinous ethical issues about the development and use of the Gadget. Perhaps it was Bob Wilson’s Quaker background that had motivated him in late 1944 to propose holding internal meetings at Los Alamos dedicated to such discussions.

  Although Oppenheimer had tried to talk him out of it, Wilson proceeded to put up notices in the lab focusing on “The Impact of the Gadget on Civilization.” Since no official records were kept about these or other scientific colloquia that discussed the possible repercussions of the bomb, accounts were based on memory. At one gathering, according to Wilson, Oppenheimer in his usual soft and riveting voice argued that the war “should not end without the world knowing about this primordial new weapon. The worse outcome would be if the Gadget remained a military secret.” At that time, Oppenheimer’s outlook had seemed logical.

  After Trinity, and more urgently, after the Japanese bombings, the younger scientists in particular wanted to be heard. On the thirtieth of August, approximately five hundred of them formed an organization called the Association of Los Alamos Scientists, known tellingly as ALAS. Within days they drafted a document emphasizing the dangers of an arms race and the need for international collaboration and cooperation, views they tackled during the Wilson meetings and views they had heard espoused by Bohr and supported by Oppenheimer. They asked Oppenheimer to forward their document to Secretary of War Stimson with an eye toward approval for publication. He did so on September 9, with an attached note indicating that though he had not participated in the writing, he was in agreement with its statements.

  That was not the case with Fermi. According to Laura, he did not endorse many of ALAS’s positions and accordingly had not joined them. For him, war was determined more by will than by weapons, by leadership rather than technical advances. He felt the times were not ripe for world government. ALAS members, regarding his decision not to join them as more a matter of temperament than of opposition to their views, did not hold it against him.

  ALAS was shocked to hear at the end of September that their document had been classified. Oppenheimer reassured its members, telling them this action was prompted by the president’s upcoming message on nuclear energy; out of courtesy, he should have the first word. On October 3, 1945, in an address to Congress, Truman promoted “directing and encouraging the use of atomic energy and all future science information toward peaceful and humanitarian ends,” thereby setting the groundwork for future international collaboration.

  Momentarily appeased, the members of ALAS again felt upended when later the same day the May-Johnson bill was proposed in Congress, establishing a nine-person commission to control atomic energy. While both civilians and military personnel were included on the commission, the bill was broadly regarded as a military power grab. Furthermore, the Los Alamos scientists were dismayed by the bill’s penalties for security violations: ten years in prison and a $
100,000 fine.

  Oppenheimer nevertheless supported the bill and quickly convinced the others on the Scientific Panel to go along with him. Leona Woods Marshall suggests that Fermi did not need convincing. He had already decided that “any change is for the worse and that a change from the military to the civilian would come into this category.”

  With the war over, ALAS no longer wanted to be under the thumb of the military or to have their freedom to exchange information curtailed unless there were very, very good reasons. Anderson, Fermi’s trusted lieutenant, voiced a typical reaction in an October 11 letter he wrote to an ALAS organizer; he thought the Scientific Panel’s members “were duped when they urged the scientists to keep silent about the army’s bill.”

  Wilson took the protest a step further by mailing the classified ALAS document directly to the New York Times; officially this was a security violation. The newspaper promptly published it on the front page. Wilson later wrote, “For me it was a declaration of independence from our leaders at Los Alamos, not that I did not continue to admire and cherish them. But the lesson we learned early on was that the Best and the Brightest, if in a position of power, were frequently constrained by other considerations and were not necessarily to be relied upon.” The politically active Wilson was not charged with a security breach and was roundly praised for bringing the issue into the public domain.

  Nobody was more consistent or more effective in opposing the May-Johnson bill than Leo Szilard. He organized, wrote, lobbied, and spoke repeatedly against military control of nuclear energy. By the end of 1945, his and others’ efforts bore fruit. The president abandoned his support of the May-Johnson bill. Connecticut’s Brien McMahon, the chairman of the newly formed Senate Special Committee on Atomic Energy, began drafting a countermeasure designed to put a civilian board in charge of nuclear energy.