From Fission Research to a Prize for Peace.
Scientific American January 1996
Joseph Rotblat believes scientists must bear a moral responsibility for their discoveries.
The building of the atomic bomb is the tale of the century. From that experience have come many stories of scientists ensnared in the web of national politics or entranced by the search for the fundamentals of the universe. There was one physicist, however, who marched to a different drummer, who left the Manhattan Project when it was discovered the Germans were not building a bomb. "The one who paused was Joseph Rotblat," the physicist Freeman Dyson once wrote, "Who, to his everlasting credit, resigned his position at Los Alamos." Joseph Rotblat left Los Alamos National Laboratory in New Me)dco in 1944, while there was still time to write a different history for this century. A nuclear physicist, Rotblat transformed his career to medical physics and passionately pursued disarmament. Last year Rotblat was awarded the Nobel Peace Prize for his efforts to eliminate nuclear weapons from the planet. A vigorous man with thinning white hair, Rotblat spoke about his decision several years ago at a meeting of Physicians for Social Responsibility in Chicago: "This was truly a choice between the devil and the deep blue sea," he said. "The very idea of working on a weapon of mass destruction is abhorrent to a true scientist; it goes against the basic ideals of science. On the other hand these very ideals were in danger of being uprooted, if-by refusing to develop the bomb-a most vile regirne were enabled to acquire world domination. I do not know of any other case in history when scientists were faced with such an agonizing quandary. "Four years after I started work on the bomb, serious doubts began to occupy my mind about this work. It became daily clearer to me that Germany, with its vastly extended military operations and crippling damage to its industry, was most unlikely to be able to build the bomb, even if its scientists hit on the right idea of how to make it. The reasons for which I sacrificed my principles were rapidly wearing off. This led me to the decision to resign from the project." Rotblat lost his wife, his home, his world, to the Nazis. Many people suffering such losses would have retreated into themselves. Instead, from reserves that few can fathom, he took on a very public career and began working for nuclear disarmament. An intensely private man, he agreed to tell me his story.
Rotblat was born in Warsaw in 1908. Tum-of-the-century Poland was a peasant nation with a veneer of sophisticated city gentry. Rotblat's parents were Jewish; his father was in the paper-transport business. Life included a pony and summers in the country. World War I ended that idyll. The family business failed. "In the basement in the house in which we were living we distilled somogonka-iMcit vodka-as a way of eaming a living," Rotblat recalled. "One had to fight for one's survival." Rotblat obtained his degree in 1932 and began research at the Radiological Laboratory of Warsaw. Working in Poland in the 1930s with few of the amenities of Ms Western European colleagues, Rotblat asked the right questions and found some of the answers. During this period, Rotblat married Tola Gryn, a student of Polish literature. In 1939 he accepted an invitation from James Chadwick to work at the University of Liverpool. liverpool's cyclotron was part of the attraction, Rotblat hoped to build one in Warsaw upon his retumjust as Rotblat was planning his trip to England, nuclear physics was thrown into turmoil. Two German chemists, Otto Hahn and Fritz Strassmann, split the uranium atom by firing neutrons at it; the process of nuclear fission resulted. The experiment had not converted lead into gold, but its consequences were as significant. A large amount of energy is released during fission. So are some neutrons. How many was crucial. If it were just a single neutron, there was little chance that the new neutron would also hit a uranium nucleus and so continue the process. But if two or more were products of the splitting, then the proba bility of a chain reaction would increase. A number of physicists around the globe, including Rotblat, set out to ftnd the answer. He soon discovered that several surplus neutrons are released from each ftssioning uranium atom-but he was beaten to publication by France's Fredric joliot-Curie. "I began to think about the consequences and the possibility that a chain reaction can proceed at a very fast rate,' Rotblat said. "Then, of course, there could be an explosion because of the enormous amount of energy produced in a short time." Rotblat traveled to England on his own, his fellowship gave him too little money for two. Six months later he received additional funds, and in late August 1939, Rotblat returned to Poland to make arrangements for his wife to join him in liverpool. He left Poland first; Tola was to join him shortly. Because there had been a partial news blackout in Poland, Rotblat and his wife were unaware of how serious the situation had become. The Nazis invaded Poland on the first of September, and the conflict was over within a few weeks. Rotblat sought transit visas for his wife through Belgium, Denmark and Italy; each time, borders closed before his wife could leave Poland. Rotblat would never see her again. Back in England, Rotblat decided the immediate danger from the Nazis was so great that "one had to put aside one's moral scruples regarding the bomb." With Chadwick's help, Rotblat began experiments in Liverpool to investigate the potential for an atomic bomb. Con ditions were not exactly easy. "Almost every night, I was doing several hours of firewatching, for incendiary bombs." Nevertheless, by 1941 British research ers had established that the bomb was theoretically possible. Although U.S. researchers had made much progress toward a self-sustaining nuclear reaction-a reactor-their efforts toward an explosive device had been stalled. The British restored the Americans' belief in the bomb. Churchill and Roosevelt agreed to set up a joint research facility in the U.S. The British team, including Rotblat, would work with the Americans. After moving to Los Alamos, Rotblat leamed of Ameri can plans for the bomb. He recalled that one night at dinner General Leslie Groves, military commander of the Manhattan Project, "mentioned that the real purpose in making the bomb was to subdue the Soviets." Rotblat began to speak with other Los Alamos physicists about not using the bomb, but the usual response was that "we started an ex periment; we must see it through." Events in Europe were overtaking the researchers. Rotblat continued, "In late 1944 Chadwick told me that an intelligence report indicated that the Germans weren't working on the bomb. A few days later I told him I wanted to leave." Threatening him with arrest should he speak about it, Los Alamos security agents kept Rotblat from discussing his decision with the other scientists. In stead he told-his colleagues that he was returning to Europe in order to be closer to his family (although he had heard nothing from them during the war). After the war ended, he discovered that his wife had perished, while his mother, sister and two brothers had survived. Rotblat returned to Liverpool at the beginning of 1945. He kept his silence until the dropping of the bombs on Japan that August. He realized that the atomic bomb "was a small beginning of something much larger. I could foresee the coming of the hydrogen bomb." He began to give talks across Britain, at tempting to convince his fellow physi cists to call a moratorium on nuclear research. Rotblat also began a transition to medical applications of physics, and within several years he moved to Saint Bartholomew's Hospital in London. His investigations of treatments for cancer led Rotbiat to studying the effects of radiation on healthy subjects with Patricia J. lindop, a physiologist. Ironically, this work led him back to the bomb. "Even in 1957, which was 12 years after the bomb, many people did not be lieve that cancer results from radiation," Rotblat said. "They used to say that orily leukemia is induced by radia tion, not other cancers. From the work I did with Lindop on mice, I could see that all sorts of cancer were produced." In 1954 Rotblat met Bertrand Rus sell, who had been growing increasing ly concemed about the dangers of the nuclear arins race. The British philosopher suggested that a group of scientists be convened for the purpose of discussing nuclear disarmament. And so Pugwash-the movement of scien tists with which Rotblat shared the Nobel Peace Prize-was born. Pugwash got its name from the Nova Scotia town I where the first meeting was held. "It was very small, with 22 people," Rotbiat reminisced. But what 22 people! The participants included three Nobel laureates, the vice president of the Soviet Academy of Sciences and a former director-general of the World Health Organization. It was an extraordinary undertaking, at a complicated time. "Anyone in the West, to come to such a meeting, to talk peace with the Russians, was con demned as a Communist dupe," Rotblat noted. "It was a risk, a gamble. It could have just broken up in disarray. As it turned out, people really spoke up and argued-but argued as scientists." The conference's brief report detailed the radiation hazards of nuclear testing, made recommendations on arms control and stated several principles of sci entists' social responsibility. The world's leaders listened. Pugwash meetings continued. In 1961, a year of high tension between East and West, a Pugwash con ference brought together the vice pres ident of the Soviet Academy of Sciences and the U.S. presidential science adviser. Afterward, they met with President John F. Kennedy and discussed a nuclear test ban. A treaty banning above ground testing of nuclear weapons was signed in 1963. Subsequent Pugwash meetings helped to pave the way for peace negotiations between the U.S. and North Vietnam in the late 1960s and for the 1972 Treaty on Anti-Ballistic Nfissile Systems between the U.S. and the U.S.S.R. For many years, Rotblat's office at Saint Bartholomew's Hospital served as Pugwash's headquarters. Rotblat or ganized the conferences, wrote histories of the movement and served as the secretary-general for 14 years. In 1988 he was elected president of Pugwash, a position he still holds. Some call him llw. Pugwash." It is easy to believe that with the end of the cold war and reductions of nu clear arsenals, Pugwash's objectives have been achieved. Rotblat knows well that the world is not so simple. The new situation has new instabilities-Russia is a prime example. Nor has the end of the cold war diminished the desire of Iraq and North Korea, for instance, to join the nuclear club. "I do not believe that a permanent di vision into those who are allowed to have nuclear weapons and those who are not is any basis for stability in the world," Rotblat declared. "Therefore, the ultimate solution is the eradication of nuclear weapons. How can we pre vent one nation from secreting a few weapons away? This is a task for scien tists, primarily a technological problem ensuring that no one is cheating." Economic considerations are also impor tant, Rotblat said: "If we are to have disarmament, we have to see that the transition from military industries to peaceful industry-the problem of con version-can be arranged so as not to cause economic upheavals." Perhaps the greatest task for Pugwash, and for all of humanity, is creating "a climate of trust and goodwill" among all the world's people. "We have to develop in each of us a sense of loyalty to mankind that wffl be an exten sion of our present loyalties to our family, our city, our nation." Scientists, who are to a large extent citizens of the world," can and should lead this educational effort, Rotblat said. Rotblat has a large classical record collection waiting for his retirement. That time has not yet come. At 87, Ws energy is that of a man half his age; he continues to lecture and attend meet ings worldwide. in December he was scheduled to travel to Oslo, Norway, for the awarding of the Nobel Prize for Peace. He has come a long way for someone whose first venture outside Poland was at the age of 30 in the spring of 1939. -Susan Landau
of a Nuclear War
Philip Morrison Scientific American Aug 95 (extract)
The Trinity test, the first test of a nuclear bomb went off as planned on July 16th 1945 , leaving life-long indelible memories. None is as vivid for me as that brief flash of heat on my face, sharp as noonday for a watcher 10 miles away in the cold desert predawn, while our own false sun rose on the earth set again.
For most of the 2,000 technical people at Los Alamos-civilians military and student-soldiers-that was was the climax of our actions. The terrifying deployment less than a month later appeared as anticlimax, out of hands, far away. The explicit seaming had hoped for never came; the nucler transformation of warfare was kept secret from the world until disclosed by the fires of Hiroshima.
Nudear War in Embryo
The three bombs of 1945-the test bomb and the two bombs dropped on Japan-were more nearly improvised pieces of complex laboratory equipment than they were reliable weaponry. We soon after the July test, some 60 of us flew from Los Alamos to the North Pacific to assist in the assembly of these complex bombs, adding our unique skills to those of scores of thousands of airmen on Tinian, where unen shiploads of gasoline and firebombs were entering the harbor. The Hiroshima bomb, first to be readied, was first to be used, on August 6, 1945. That city was turned to rust-red ruin by the uranium bomb nicknamed Little Boy. The design had never been tested before it was dropped, as the gun design was so simple, though much costlier in nuclear fuel. Then the second version of the just tested plutonium implosion bomb Fat Man brought disaster to Nagasaki. The war soon ended. With the sense that I was completing my long witness to the entire tragedy, I accepted the assignment to join the preliminar-American party hurriedly sent from our Pacific base to enter Japan on the first day of U.S. occupation. Joined by two other young Americans in uniform, I traveled by train for a couple of weeks across Japan, the rails crowded with demobilizing troops. The Japanese were disastrously impoverished and hungry, yet still orderly. Along the tracks, we saw cities large and small, ruined by 100 wildfires set with jelly gasoline by raids of up to 1,000 B-29 bonibers, devastation that was the very mark of the old war. The damage in these other cities resembled the destruction visited on Hiroshima by one single nuclear explosion and its aftermath of fire. We had loosed our new kind of war, nuclear war in embryo, with only two bombs. A single bomber was now able to destroy a good-size city, leaving hundreds of thousands dead. Yet there on the ground, among all those who cruelly suffered and died, there was not all that much difference between old fire and new. Both ways brought unimagined inferno. True, we saw hundreds of people lying along the railway platform at Hiroshima; most of them would die from burns or from the new epidemic of radiation sickness that we had sowed. But many other cities, including fire-bombed Tokyo, where 100,000 or more had died in the first fire raid, also counted hosts of burned and scarred survivors. Radiation is no minor matter, but the difference between the all-out raids made on the cities of Japan and those two nuclear attacks remains less in the nature or the scale of the human tragedy than in the chilling fact that now it was much easier to destroy the populous cities of humankind. Two nuclear bombs had perhaps doubled the death count brought by air power to Japan. Fission and then fusion offered havoc wholesale, on the cheap. It was not World War II that the atom's nucleus would most transform but the next great war. The past 50 years have been ruled by one nuclear truth. In 1945 the U.S. deployed about 1,000 long-range B-29s. By the 1960s we had about 2,000 jet bombers, and by the 1980s maybe 1,500 missiles. For more than four decades we kept a striking force comparable with the one General Curtis E. Le-May commanded in 1945, each year becoming faster, more reliable, and so on.
But now every single payload was not chemical explosive but nuclear fire, bringing tens or even hundreds of times greater death and destruction. The statesmen on both sides chose to arm and even threaten war with these weapons, a war that would be orders of magnitude more violent than all before it. Yet the statesmen did not follow through on their threats; large-scale nuclear conflict is now recognized for what it is, wholly intolerable. I returned from Japan at the end of September 1945 to learn that one young man within our small group was gone, killed in the lab by a runaway radiation burst. (He would not be the last, either.) Our temerity about the nuclear dragon had left its legacy in New Mexico as well. America was at peace but clamorous, the new atomic bomb, in all its terror, the center of interest. By the end of the year many scientists, including myself, made clear, concerted, even dramatic public statements about the future of nuclear war. What we said then was this: Secrecy will not defend us, for atoms and skills are everywhere. No defenses are likely to make up for the enormous energy release; it will never be practical to intercept every bomb, and even a few can bring grave disaster. Passive shelter is little use, for the deeper the costly shelter, the bigger the inexpensive bomb. No likely working margin of technical superiority wifl defend us either, for even a smaller nuclear force can wreak its intolerable damage.
Legacy of the Bomb
I think these views are as right today as they were in 1945. Only one way remains: comprehensive international agreement for putting an end to nuclear war, worked out in rich detail. It is striking that the laboratory leaders of the Manhattan Project said much the same thing as early as August 17, 1945, three days after the peace was made with Japan. But they wrote in secret to the U.S. secretary of war, and their first views remained hidden for many years. The 1990s have given us an unexpected historical opportunity, as unexpected as was fission itself. The U.S. and the former Soviet Union are right now dismantling some eight or 10 nuclear warheads every day, yet both have a long way to go. We have never had so promising and so concrete an omen of peace, but it is still mainly promise. We need resolute and widespread action. The task is not simple, but was any international goal more important than securing the future against nuclear war? How could we ever have planned war with tens of thousands of nuclear warheads? Did we not know that America would lie in ruin as well? With nuclear weapons, war achieves a final, futile symmetry of mutual destruction. In 1963 Oppenheimer recalled that when Bohr first came to Los Alamos during the war, the visitor asked his friend and host very seriously: "Is it big enough?" Oppenheirner knew just what Bohr meant. Was this new scale of warfare big enough to challenge the of war itself ? "I don't know if it was then" Oppenheimer wrote, "but "but finally it did become big enough". Then it became frighteningly too big and it is still far too big, but at least it is no longer luxuriantly growing. We can if we persist, end its unparallelled threat.