The Apocalypse Factory
Page 12
The physicists in Los Alamos were confident that a gun-type bomb using uranium-235 would work, but the amount of material required posed a big problem. Even in the spring of 1945, the separation of uranium-235 from natural uranium ore was not going well. Groves would be lucky to have enough uranium for a single gun-type bomb by that summer, and he wouldn’t have enough for another gun-type bomb before the end of the year. Even if the Los Alamos scientists had wanted to test the gun-type bomb, they didn’t have enough uranium to do so.
The possibility of making an atomic bomb with one-tenth as much fissile material changed everything. If implosion worked, Hanford should be able to manufacture enough plutonium for a bomb by the middle of the summer. After that, Hanford should be able to produce enough plutonium for several bombs per month. If the Manhattan Project had been forced to stick with gun-type bombs, the United States might have had a single atomic weapon by the summer of 1945. With the development of implosion, it could make as many bombs as it wanted.
Still, implosion was far from a sure thing. The scientists and engineers at Los Alamos were not at all confident that they could get it to work. They certainly couldn’t see setting off the very first implosion-based bomb in combat. They would need to test one first. Groves immediately objected. He needed a bomb as soon as possible. The project could not waste plutonium on an unnecessary test.
The bomb makers persisted. The United States could not risk dropping a dud, and Hanford would be able to make enough plutonium for a second bomb in a couple of weeks. Groves knew they were right about the test. If he dropped a bomb on Japan that didn’t work, his reputation would be ruined. Plus, he was thinking by this time about what would happen after the war, when the United States would be the only country with nuclear weapons. In 1944, a Manhattan Project scientist had been startled to hear Groves admit that the development of atomic bombs was really meant to subdue the Soviet Union, because the United States would have nuclear weapons after the war and the Soviets would not. If implosion could be developed, it would make possible a virtually unlimited supply of atomic bombs. Yes, a test was a small price to pay for access to such a valuable technology.
AS THE ALLIES PREPARED for the invasion of France in the late spring of 1944, Crawford Greenewalt became increasingly worried that the Germans would use atomic bombs to fend off the Allied troops. “I don’t think I’ll ever forget D-Day,” he recalled many years later. “I was actually afraid to look at the newspapers, because with our troops concentrated on the beaches of France, and with the enormous concentration of men and material, I thought, ‘Well, if the Germans really have it, here it comes.’” Groves was worried about something else. If the Germans had built a reactor and were using it to make plutonium, they could produce large quantities of radioactive materials to drop on invading troops. He convinced Eisenhower to have several soldiers carry radiation detectors onto the Normandy beaches on June 6, though no radiation or any other nuclear devices were detected.
Groves never had any hard evidence that the Germans were working on an atomic bomb. The US government based the entire Manhattan Project on hearsay, speculation, and worst-case scenarios. Nevertheless, Groves did not have good evidence that the Germans were not working on a bomb, and as the Allied troops made their way deeper into Europe, he continued to worry about German nuclear weapons. Earlier, he had approved the establishment of a covert counterintelligence group that came to be known by the name Alsos, though Groves was infuriated when he learned about the name, since alsos is the Greek word for a grove of trees. The civilian component of the operation was headed by Samuel Goudsmit, an accomplished nuclear physicist from the University of Michigan. Born in the Netherlands and fluent in several languages, Goudsmit had been working on radar during World War II and knew little about the Manhattan Project. That appealed to Groves—he would have little to tell the Germans if he were captured. Goudsmit also had plenty of incentive to fight. In March 1943, he had received a letter from his Jewish parents, who had been living in The Hague before the war. Instead of a return address in the Netherlands, the envelope bore the site of a Nazi concentration camp. Its purpose: to bid their son farewell.
After D-Day, the Alsos team followed the Allied troops into Europe, looking for any hint of a German atomic bomb. Records gathered in Brussels indicated that Germany had procured large shipments of uranium in 1942 and 1943, which greatly concerned Groves. Could the Germans, even as their war-fighting ability crumbled, be working on one last stand?
Further documents indicated that Strasbourg had been one location of German nuclear research. As soon as the US Army entered the city in late November, Goudsmit followed. There, he worked for four days and nights by candlelight, under oppressive air raids, reading the captured papers of University of Strasbourg physicist Carl Friedrich von Weizsäcker. Here was just what he needed. The papers revealed that the Germans had been unable to extract large quantities of uranium-235 from their materials. They had tried to build a reactor in 1944, but they had failed to produce a chain reaction. “The conclusions were unmistakable,” Goudsmit later reflected. “The evidence at hand proved definitely that Germany had no atomic bomb and was not likely to have one in any reasonable time.” He and his Alsos team related the recovered information in “The Strasbourg Report,” which they jubilantly shipped back to Groves.
Groves wasn’t satisfied. He considered the Strasbourg information too easily gathered and wondered if it had been planted. Furthermore, the information meant that the German scientists had been working on a bomb, which meant that they still could be working on a bomb somewhere inside Germany. He ordered the Alsos investigators to keep looking.
Throughout the first part of 1945, the Alsos team followed the army as it penetrated deeper into Germany. In Stadtilm, they found eight tons of uranium oxide and documents describing the German nuclear program. They began to capture scientists who had worked on nuclear energy during the war, though none provided much information. In the small town of Haigerloch, an Alsos team found a small experimental nuclear reactor made of graphite blocks, though it did not contain any heavy water or uranium. Only on April 23, after the capture of 1,200 tons of uranium ore hidden in caves near Strassfurt, was Groves able to write to Army Chief of Staff George Marshall: “The capture of this material, which was the bulk of uranium supplies available in Europe, would seem to remove definitely any possibility of the Germans making any use of an atomic bomb in this war.”
Compared with the Manhattan Project, the German nuclear program was laughably amateurish. “The whole German uranium setup was on a ludicrously small scale,” Goudsmit later wrote. “All it amounted to was a little underground cave, a wing of a small textile factory, a few rooms in an old brewery. . . . Sometimes we wondered if our government had not spent more money on our intelligence mission than the Germans had spent on their whole project.”
The German nuclear program never got off the ground for a variety of reasons. An early measurement that neglected to account for impurities indicated that graphite would make a poor moderator in a reactor. Instead, the Germans decided to use heavy water as a moderator, which was so technically difficult that they never did get a reactor to work. Other problems were administrative. The Germans never found someone like Groves to unify and lead the program forward, and much of the top scientific talent in Germany had fled to the United States to avoid Nazi persecution. Hitler was obsessed with other weapons, including the V-2 ballistic missile, and never embraced a nuclear program, as Roosevelt had done. And, as nuclear historian Alex Wellerstein has observed, German scientists never believed that the United States would be capable of building atomic bombs; they “lacked the fear of an Allied project that the Allies had of them.”
The US military never got to the point of considering where or how atomic bombs might be used in Europe. Nor was the idea of dropping such bombs on Europe ever thought through carefully. Would a US president be willing to destroy European cities or large portions of the countryside with a sin
gle bomb? And if a weapon were dropped and failed to detonate, the Germans would have a ready supply of uranium, manufactured in Oak Ridge, or plutonium, manufactured in Hanford, to use in their own bomb.
But even if the German nuclear program had never been a serious threat, the war was far from over in early 1945. In the Pacific, US forces were struggling to take Iwo Jima and then Okinawa. If those battles were successful and the Japanese still refused to surrender, the Allies might need to invade the Japanese mainland. Even though atomic bombs were not needed against Germany, they could prove useful elsewhere.
In early 1945, when he finally had demonstrated that the German atomic bomb project had made little progress, Goudsmit remarked to his Alsos colleague Robert Furman. “Isn’t it wonderful that the Germans have no atom bomb? Now we won’t have to use ours.”
“Of course you understand, Sam,” replied Furman, who had worked with Groves before the war, “if we have such a weapon, we are going to use it.”
Chapter 13
WASHINGTON, DC
GENERAL GROVES NEEDED MORE PLUTONIUM. IN THE SPRING OF 1945, Hanford was not producing enough material for both a test bomb and bombs to use in the war. The operators were still learning how best to work their massive reactors and separation plants. For Groves to have enough nuclear material for more than one bomb before the end of the war, Hanford had to work faster.
On March 24, he arrived in Richland with a contingent of DuPont engineers, and “a discussion was held as to the production schedule to be followed in the coming few months,” Matthias wrote in his journal. Groves and Matthias had three possible ways of speeding up plutonium production. First, they could run the reactors at more than their design power, which would convert more uranium in each fuel element into plutonium. Second, they could run more fuel through the reactors, increasing the amount of uranium exposed to the reactors’ neutrons. Third, they could reduce the cooling-off period before the irradiated fuel elements entered the separation plants, allowing the plutonium to be extracted sooner.
By the beginning of April, Groves and Matthias were using all three approaches. “Production results have been extremely good,” Matthias wrote of what came to be known as the speedup, “and the time of delivery of units has been faster than originally planned.” But the speedup exacted a severe environmental toll. Uranium that spent less time in the reactor contained less plutonium, so more of it had to be processed. The streams of radioactive chemicals flowing into the steel tanks near the processing plants swelled. Worse, cooling the fuel elements for just a few days gave the radioactive fission products less time to decay. The levels of radioactive gases billowing from the stacks next to the separation stacks skyrocketed.
Matthias had long since given up hand-delivering the plutonium to Los Alamos. It now traveled in olive-green panel trucks that looked like ambulances. Convoys of five vehicles and 10 men equipped with shotguns, revolvers, and machine guns traveled from Richland through Boise to Salt Lake City, where another group met the Hanford group to take the plutonium to Los Alamos. In case of a wreck or a fire, the men were told to “get the hell out of the road and get upwind,” recalled one of the couriers. As Los Alamos got more and more desperate for plutonium, Matthias threw caution to the wind. By the summer of 1945, the plutonium was flying to Santa Fe on C-47 transport planes.
ON APRIL 12, 1945, Franklin Roosevelt was sitting in the living room of his retreat in Warm Springs, Georgia, having his portrait painted. He had come there two weeks earlier to escape the strain of the presidency and World War II, which had left him exhausted and frail. Shortly after 1:00 p.m., he complained of a terrific pain in the back of his head and passed out. A doctor arrived and recognized that the president had suffered a massive cerebral hemorrhage. He gave Roosevelt a shot of adrenaline in the heart to try to revive him. But by the middle of the afternoon, the president was dead.
When Eleanor Roosevelt met with Harry Truman that evening to tell him that her husband was dead and that he would now be president, Truman asked if he could do anything for her. She replied by asking if she could do anything for him. “You are the one in trouble now.” After being selected as Roosevelt’s surprise pick for vice president in 1944, Truman had met with the president just a handful of times, usually in the company of other government officials. Roosevelt hadn’t even told him about the Manhattan Project. A few years earlier, as chair of the Committee on Military Affairs in the Senate, Truman had started to investigate the mysterious federal acquisition of property in Washington State. He backed off when Secretary of War Stimson told him that the land was needed for a top-secret military project.
On April 25, Groves and Stimson met with Truman in the Oval Office to brief him on atomic bombs. At this point, Stimson was the grand old man of Washington policymakers. Born in 1867, educated at Phillips Academy, Yale, and Harvard, he was a product of the 19th century who was being forced to deal with the most vexing problem of the 20th. He had been working with Vannevar Bush and James Conant—still the government’s most powerful academic advisors through their leadership of the federal Office of Scientific Research and Development—on a plan for the postwar control of nuclear technologies, and the memo he handed to President Truman reflected these discussions. “Within four months,” the memo began, “we shall in all probability have completed the most terrible weapon ever known in human history, one bomb of which could destroy a whole city.” The United States could not restrict other nations from building atomic bombs, though probably the only nation that could do so soon would be the Soviet Union. The United States therefore needed to consider the international control of nuclear technologies once the existence of atomic bombs became known. The memo called for the establishment of a committee that could recommend actions to prepare for the war’s end. US leadership in the development of atomic bombs “has placed a certain moral responsibility upon us which we cannot shirk without very serious responsibility for any disaster to civilization which it would further,” Stimson’s memo stated.
Groves then handed the president a 23-page memo entitled “Atomic Fission Bombs.” Truman objected that he was too busy to read such a long document, but Groves and Stimson insisted, and Truman acquiesced. The memo said that a gun-type bomb using uranium would likely be ready by about August 1, with a second gun-type bomb ready by the end of the year. But an implosion-type bomb would be tested in July and could be used against Japan in August, with new implosion bombs becoming available about every 10 days thereafter. “While the project’s primary mission is the development of atomic bombs for use against Japan the tremendous and far reaching implications of the future cannot be and have not been overlooked.” Drawing on the thinking of Bush and Conant, the memo concluded: “Atomic energy, if controlled by the major peace-loving nations, should insure the peace of the world for decades to come. If misused it can lead our civilization to annihilation.”
In their post-meeting notes, both Stimson and Groves congratulated themselves on how well the meeting had gone. Truman had approved their plans and appeared to be enthusiastic about the new weapons. Now Groves just needed to prove that his $2 billion bombs would work.
A WEEK LATER, Truman established the committee Stimson had requested in his memo. Named the Interim Committee, since new arrangements would be inevitable once atomic bombs became public knowledge, its eight members were all civilians: Stimson was the chair, with George Harrison, his special assistant at the War Department, serving as deputy chair. Undersecretary of the Navy Ralph Bard and Assistant Secretary of State William Clayton—both, like Harrison, former businessmen who had responded to Roosevelt’s requests to serve in government—represented two government agencies that would be particularly affected by the development of atomic bombs. Bush, Conant, and Karl Compton, president of the Massachusetts Institute of Technology (and Arthur Compton’s brother), represented academia. The final member, serving as President Truman’s personal representative, was James Byrnes, a former senator from South Carolina whom Truman woul
d soon name secretary of state. Groves was not on the committee, but he attended all its meetings, providing information and subtly steering the committee in directions he wanted it to take.
At the committee’s second meeting on May 14, it decided to create a scientific advisory group that “should be free not only to discuss technical matters but also to present to the Committee their views concerning the political aspects of the problem,” as the meeting notes put it. The four members of the panel were Arthur Compton, still at the Met Lab in Chicago; Enrico Fermi, who by this time had relocated to Los Alamos; Ernest Lawrence at the University of California, Berkeley; and the director of the Los Alamos laboratory, Robert Oppenheimer.
Attendance was spotty at most of the Interim Committee’s meetings, but all its members were there for the committee’s only meeting with the Scientific Panel on May 31, 1945. At 10:00 a.m., Stimson opened the meeting, which took place in a conference room in the Pentagon, by praising “the brilliant and effective assistance rendered to the project by the scientists of the country.” The development of nuclear energy marked “a new relationship of man to the universe,” Stimson said, that “might be compared to the discoveries of the Copernican theory and of the laws of gravity, but far more important than these in its effects on the lives of men.” Then the committee and its Scientific Panel got down to work.
As Oppenheimer explained, the bombs being prepared at Los Alamos would have an explosive force of between 2,000 and 20,000 tons of TNT. The wide uncertainty in the estimate came not from the uranium bomb, which physicists were sure would produce an explosion about in the middle of that range, but from the implosion bomb. Until it could be tested, no one knew whether implosion would produce a relatively small explosion or something much bigger. Beyond their destructive power, Oppenheimer emphasized the psychological and health impacts of nuclear weapons. They would produce a “brilliant luminescence” that would rise two to four miles into the air. In addition, they would shower their surroundings with neutrons “dangerous to life for a radius of at least two-thirds of a mile.”