Szilard transmitted the letter in its final form to Sachs on August 15 along with a memorandum of his own that elaborated on the letter’s discussion of the possibilities and dangers of fission. He had not given up contacting Lindbergh—he drafted a letter to the aviator the following day—but he seems to have decided to try Sachs in the meantime, probably in the interest of moving the project on; he pointedly asked Sachs either to deliver the letter to Roosevelt or to return it.1190
One of the discussions Szilard had added to the longer draft that Einstein chose concerned who should serve as liaison between “the Administration and the group of physicists working on chain reactions in America.”1191 In his letter of transmittal to Sachs, Szilard now tacitly offered himself for that service. “If a man, having courage and imagination, could be found,” he wrote, “and if such a man were put—in accordance with Dr. Einstein’s suggestion—in the position to act with some measure of authority in this matter, this would certainly be an important step forward. In order that you may be able to see of what assistance such a man could be in our work, allow me please to give you a short account of the past history of the case.”1192 The short account that followed, an abbreviated and implicit curriculum vitae, essentially outlined Szilard’s own role since Bohr’s announcement of the discovery of fission seven crowded months earlier.
Szilard’s offer was as innocent of American bureaucratic politics as it was bold. It was surely also the apotheosis of his drive to save the world. By this time the Hungarians at least believed they saw major humanitarian benefit inherent in what Eugene Wigner would describe in retrospect as “a horrible military weapon,” explaining:1193
Although none of us spoke much about it to the authorities [during this early period]—they considered us dreamers enough as it was—we did hope for another effect of the development of atomic weapons in addition to the warding off of imminent disaster. We realized that, should atomic weapons be developed, no two nations would be able to live in peace with each other unless their military forces were controlled by a common higher authority. We expected that these controls, if they were effective enough to abolish atomic warfare, would be effective enough to abolish also all other forms of war. This hope was almost as strong a spur to our endeavors as was our fear of becoming the victims of the enemy’s atomic bombings.
From the horrible weapon which they were about to urge the United States to develop, Szilard, Teller and Wigner—“the Hungarian conspiracy,” Merle Tuve was amused to call them—hoped for more than deterrence against German aggression.1194 They also hoped for world government and world peace, conditions they imagined bombs made of uranium might enforce.
* * *
Alexander Sachs intended to read aloud to the President when he met with him. He believed busy people saw so much paper they tended to dismiss the printed word. “Our social system is such,” he told a Senate committee in 1945, “that any public figure [is] punch-drunk with printer’s ink. . . .1195 This was a matter that the Commander in Chief and the head of the Nation must know. I could only do it if I could see him for a long stretch and read the material so it came in by way of the ear and not as a soft mascara on the eye.” He needed a full hour of Franklin Delano Roosevelt’s time.
History intervened to crowd the President’s calendar. Having won the Rhineland, Austria and Czechoslovakia simply by taking them, having signed the Pact of Steel with Italy on May 22 and a ten-year treaty of nonaggression and neutrality with the USSR on August 23, Adolf Hitler ordered the invasion of Poland beginning at 4:45 A.M. on September 1, 1939, and precipitated the Second World War. The German invasion fielded fifty-six divisions against thirty Polish divisions strung thinly across the long Polish frontier; Hitler had ten times the aircraft, including plentiful squadrons of Stuka dive-bombers, and nine divisions of Panzer tanks against Polish horse cavalry armed with swords and spears. The assault was “a perfect specimen of the modern Blitzkrieg,” writes Winston Churchill: “the close interaction on the battlefield of army and air force; the violent bombardment of all communications and of any town that seems an attractive target; the arming of an active Fifth Column; the free use of spies and parachutists; and above all, the irresistible forward thrusts of great masses of armour.”1196
The mathematician Stanislaw Ulam had just returned from visiting Poland, bringing with him on a student visa his sixteen-year-old brother, Adam:
Adam and I were staying in a hotel on Columbus Circle. It was a very hot, humid, New York night. I could not sleep very well. It must have been around one or two in the morning when the telephone rang. Dazed and perspiring, very uncomfortable, I picked up the receiver and the somber, throaty voice of my friend the topologist Witold Hurewicz began to recite the horrible tale of the start of war: “Warsaw has been bombed, the war has begun,” he said. This is how I learned about the beginning of World War II. He kept describing what he had heard on the radio. I turned on my own. Adam was asleep; I did not wake him. There would be time to tell him the news in the morning. Our father and sister were in Poland, so were many other relatives. At that moment, I suddenly felt as if a curtain had fallen on my past life, cutting it off from my future. There has been a different color and meaning to everything ever since.1197
One of Roosevelt’s first acts was to appeal to the belligerents to refrain from bombing civilian populations. Revulsion against the bombing of cities had grown in the United States since at least the Japanese bombing of Shanghai in 1937.1198 When Spanish Fascists bombed Barcelona in March 1938, Secretary of State Cordell Hull had condemned the atrocity publicly: “No theory of war can justify such conduct,” he told reporters. “ . . . I feel that I am speaking for the whole American people.”1199 In June the Senate passed a resolution condemning the “inhuman bombing of civilian populations.”1200 As war approached, revulsion began to give way to impulses of revenge; in the summer of 1939 Herbert Hoover could urge an international ban on the bombing of cities and still argue that “one of the impelling reasons for the unceasing building of bombing planes is to prepare reprisals.”1201 Bombing was bad because it was enemy bombing. Scientific American saw through to a darker truth: “Although . . . aerial bombing remains an unknown, indeterminate quantity, the world may be sure that the unwholesome atrocities which are happening today are but curtain raisers on insane dramas to come.”1202
So although Roosevelt had asked Congress for increased funds for long-range bombers nine months before, in appealing to the belligerents on September 1, 1939, he could still articulate the moral indignation of millions of Americans:
The ruthless bombing from the air of civilians in unfortified centers of population during the course of the hostilities which have raged in various quarters of the earth during the past few years, which has resulted in the maiming and in the death of thousands of defenseless men, women and children, has sickened the hearts of every civilized man and woman, and has profoundly shocked the conscience of humanity.1203
If resort is had to this form of inhuman barbarism during the period of the tragic conflagration with which the world is now confronted, hundreds of thousands of innocent human beings who have no responsibility for, and who are not even remotely participating in, the hostilities which have now broken out, will lose their lives. I am therefore addressing this urgent appeal to every Government which may be engaged in hostilities publicly to affirm its determination that its armed forces shall in no event, and under no circumstances, undertake the bombardment from the air of civilian populations or of unfortified cities, upon the understanding that these same rules of warfare will be scrupulously observed by all of their opponents. I request an immediate reply.
Great Britain agreed to the President’s terms the same day. Germany, busy bombing Warsaw, concurred on September 18.
The invasion of Poland brought Britain and France into the war on September 3. Abruptly Roosevelt’s schedule filled to overflowing. In early September in particular he was working overtime with a reluctant Congress to revise the
Neutrality Act to terms more favorable to Britain; Sachs was unable even to discuss arranging an interview until after the first week in September.
* * *
By September Kurt Diebner’s new War Office department had consolidated German fission research under its authority. Diebner enlisted a young Leipzig theoretician named Erich Bagge and together the two physicists planned a secret conference to consider the feasibility of a weapons project.1204 They had the authority to enlist the services of any German citizen they wished and they used it, sending out papers that left Hans Geiger, Walther Bothe, Otto Hahn and a number of other exceptional older men nervously uncertain if they were being invited to Berlin for consultation or ordered to active military service.
At the conference in Berlin on September 16 the physicists learned that German intelligence had discovered the beginnings of uranium research abroad—meaning, presumably, in the United States and Britain. They discussed the long, thorough theoretical paper by Niels Bohr and John Wheeler, “The mechanism of nuclear fission,” that had been published in the September Physical Review and especially its conclusion, which Bohr and Wheeler had elaborated from Bohr’s Sunday-morning graph work, that U235 was probably the isotope of uranium responsible for slow-neutron fission.1205 Hahn like Bohr argued that isotope separation was difficult to the point of impossibility. Bagge proposed calling in Werner Heisenberg, his superior at Leipzig, to adjudicate.
Heisenberg therefore attended a second Berlin conference on September 26 and discussed two possible ways to harness the energy from fission: by slowing secondary neutrons with a moderator to make a “uranium burner” and by separating U235 to make an explosive. Paul Harteck, the Hamburg physicist who had written the War Office the previous April, traveled to the second conference armed with a paper he had just finished on the importance of layering uranium and moderator to avoid the U238 capture resonance—the same insight that had come independently to Fermi and Szilard in early July. Harteck’s study, however, considered using heavy water as moderator, even though Harteck had worked with Rutherford at the Cavendish and knew from personal experience how expensive heavy-water production could be—water in which deuterium replaced hydrogen had to be tediously distilled from tons of ordinary H20.
Diebner and Bagge had outlined for the second conference a “Preparatory Working Plan for Initiating Experiments on the Exploitation of Nuclear Fission.”1206 Heisenberg would head up theoretical investigation. Bagge would measure deuterium’s cross section for collision to establish how effectively heavy water might slow secondary neutrons. Harteck would look into isotope separation. Others would experiment to determine other significant nuclear constants. The War Office would take over the Kaiser Wilhelm Institute of Physics, finished in 1937 and beautifully equipped. Adequate funds would be forthcoming.
The German atomic bomb project was well begun.
It may have been no less complicated by humanitarian ambiguities than the project the Hungarians in the United States proposed. One young but highly respected German physicist involved in the work from near the beginning was Carl Friedrich von Weizsäcker, the son of the German Undersecretary of State. In a 1978 memoir von Weizsäcker remembers discussing the possibility of a bomb with Otto Hahn in the spring of 1939. Hahn opposed secrecy then partly on the grounds of scientific ethics but also partly because he “felt that if it were to be made, it would be worst for the entire world, even for Germany, if Hitler were to be the only one to have it.” Like Szilard, Teller and Wigner, von Weizsäcker remembers realizing in discussions with a friend “that this discovery could not fail to radically change the political structure of the world”:1207
To a person finding himself at the beginning of an era, its simple fundamental structures may become visible like a distant landscape in the flash of a single stroke of lightning. But the path toward them in the dark is long and confusing. At that time [i.e., 1939] we were faced with a very simple logic. Wars waged with atom bombs as regularly recurring events, that is to say, nuclear wars as institutions, do not seem reconcilable with the survival of the participating nations. But the atom bomb exists. It exists in the minds of some men. According to the historically known logic of armaments and power systems, it will soon make its physical appearance. If that is so, then the participating nations and ultimately mankind itself can only survive if war as an institution is abolished.
Both sides might work from fear of the other. But some on both sides would be working also paradoxically believing they were preparing a new force that would ultimately bring peace to the world.
* * *
As September extended its violence Szilard grew impatient. He had heard nothing from Alexander Sachs. Pursuing Sachs’ previous suggestions and his own leads, he arranged for Eugene Wigner to give him a letter of introduction to MIT president Karl T. Compton; recontacted a businessman of possible influence whom he had once interested in the Einstein-Szilard refrigerator pump; read a newspaper account of a Lindbergh speech and reported to Einstein that the aviator “is in fact not our man.”1208 Finally, the last week in September, he and Wigner visited Sachs and found to their dismay that the economist still held Einstein’s letter. “He says he has spoken repeatedly with Roosevelt’s secretary,” Szilard reported to Einstein on October 3, “and has the impression that Roosevelt is so overburdened that it would be wiser to see him at a later date. He intends to go to Washington this week.” The two Hungarians were ready to start over: “There is a distinct possibility that Sachs will be of no use to us. If this is the case, we must put the matter in someone else’s hands. Wigner and I have decided to accord Sachs ten days’ grace. Then I will write you again to let you know how matters stand.”1209
But Alexander Sachs did indeed travel to Washington, not that week but the next, and on Wednesday, October 11, presented himself, probably in the late afternoon, at the White House.1210 Roosevelt’s aide, General Edwin M. Watson, “Pa” to Roosevelt and his intimates, sitting with his own executive secretary and military aide, reviewed Sachs’ agenda.1211 When he was convinced that the information was worth the President’s time, Watson let Sachs into the Oval Office.
“Alex,” Roosevelt hailed him, “what are you up to?”1212
Sachs liked to warm up the President with jokes. His sense of humor tended to learned parables. Now he told Roosevelt the story of the young American inventor who wrote a letter to Napoleon.1213 The inventor proposed to build the emperor a fleet of ships that carried no sail but could attack England in any weather. He had it in his power to deliver Napoleon’s armies to England in a few hours without fear of wind or storm, he wrote, and he was prepared to submit his plans. Napoleon scoffed: ships without sails? “Bah! Away with your visionists!”1214
The young inventor, Sachs concluded, was Robert Fulton. Roosevelt laughed easily; probably he laughed at that.
Sachs cautioned the President to listen carefully: what he had now to impart was at least the equivalent of the steamboat inventor’s proposal to Napoleon. Not yet ready to listen, Roosevelt scribbled a message and summoned an aide. Shortly the aide returned with a treasure, a carefully wrapped bottle of Napoleon brandy that the Roosevelts had preserved in the family for years. The President poured two glasses, passed one to his visitor, toasted him and settled back.
Sachs had made a file for Roosevelt’s reading of Einstein’s letter and Szilard’s memorandum. But neither document had suited his sense of how to present the information to a busy President. “I am an economist, not a scientist,” he would tell friends, “but I had a prior relationship with the President, and Szilard and Einstein agreed I was the right person to make the relevant elaborate scientific material intelligible to Mr. Roosevelt. No scientist could sell it to him.”1215, 1216 Sachs had therefore prepared his own version of the fission story, a composite and paraphrase of the contents of the Einstein and Szilard presentations. Though he left those statements with Roosevelt, he read neither one of them aloud. He read not Einstein’s subsequently famous letter but h
is own eight-hundred-word summation, the first authoritative report to a head of state of the possibility of using nuclear energy to make a weapon of war.1217 It emphasized power production first, radioactive materials for medical use second and “bombs of hitherto unenvisaged potency and scope” third. It recommended making arrangements with Belgium for uranium supplies and expanding and accelerating experiment but imagined that American industry or private foundations would be willing to foot the bill. To that end it proposed that Roosevelt “designate an individual and a committee to serve as a liaison” between the scientists and the Administration.
Sachs had intentionally listed the peaceful potentials of fission first and second among its prospects.1218 To emphasize the “ambivalence” of the discovery, he said later, the “two poles of good and evil” it embodied, he turned near the end of the discussion to Francis Aston’s 1936 lecture, “Forty Years of Atomic Theory”—it had been published in 1938 as part of a collection, Background to Modern Science, which Sachs had brought along to the White House—where the English spectroscopist had ridiculed “the more elderly and apelike of our prehistoric ancestors” who “objected to the innovation of cooked food and pointed out the grave dangers attending the use of the newly discovered agency, fire.”1219 Sachs read the entire last paragraph of the lecture to Roosevelt, emphasizing the final sentences:1220
Personally I think there is no doubt that sub-atomic energy is available all around us, and that one day man will release and control its almost infinite power. We cannot prevent him from doing so and can only hope that he will not use it exclusively in blowing up his next door neighbor.