glorification of Soviet Russia it includes, I cannot bring myself to sign it.” Einstein had gone on in that letter to denounce Russia, where “there seems to be complete suppression of the individual and of freedom of speech.” Nevertheless, Hoover implied that Einstein had supported the conference and was thus pro- Soviet.20
Hoover’s letter had six more paragraphs making similar allegations about a variety of alleged Einstein associations, ranging from pacifist groups to those supporting Spain’s loyalists. Appended was a biographical sketch filled with trivial misinformation (“has one child”) and wild allegations. It called him “an extreme radical,” which he certainly was not, and said he “has contributed to communist magazines,” which he hadn’t. General Miles was so taken aback by the memo that he wrote a note in the margin, warning, “There is some possibility of flameback” if it ever leaked.21
The conclusion of the unsigned biographical sketch was stark: “In view of this radical background, this office would not recommend the employment of Dr. Einstein on matters of a secret nature, without a very careful investigation, as it seems unlikely that a man of his background could, in such a short time, become a loyal American citizen.” In a memo the following year, it was reported that the Navy had assented to giving Einstein a security clearance, but “the Army could not clear.”22
Just as the Army’s decision was being made, Einstein was in fact eagerly doing something the likes of which he had not done for forty years, ever since he had saved up his money so that he could become a Swiss citizen after leaving Germany. He was voluntarily and proudly becoming a citizen of the United States, a process that had begun five years earlier when he sailed to Bermuda so that he could return on an immigration visa. He still had his Swiss citizenship and passport, so he did not need to do this. But he wanted to.
He took his citizenship test on June 22, 1940, in front of a federal judge in Trenton. To celebrate the process, he agreed to give a radio interview as part of the immigration service’s
It was an inspiring day, partly because Einstein showed just what type of free-speaking citizen he would be. In his radio talk, he argued that, to prevent wars in the future, nations would have to give up some of their sovereignty to an armed international federation of nations. “A worldwide organization cannot insure peace effectively unless it has control over the entire military power of its members,” he said.24
Einstein passed his test and he was sworn in—along with his step-daughter Margot, his assistant Helen Dukas, and eighty-six other new citizens—on October 1. Afterward, he praised America to the reporters covering his naturalization. The nation, he said, would prove that democracy is not just a form of government but “a way of life tied to a great tradition, the tradition of moral strength.” Asked if he would renounce other loyalties, he joyously declared that he “would even renounce my cherished sailboat” if that were necessary.25 It was not, however, necessary for him to renounce his Swiss citizenship, and he did not.
When he first arrived in Princeton, Einstein had been impressed that America was, or could be, a land free of the rigid class hierarchies and servility in Europe. But what grew to impress him more—and what made him fundamentally such a good American but also a controversial one—was the country’s tolerance of free thought, free speech, and nonconformist beliefs. That had been a touchstone of his science, and now it was a touchstone of his citizenship.
He had forsaken Nazi Germany with the public pronouncement that he would not live in a country where people were denied the freedom to hold and express their own thoughts. “At that time, I did not understand how right I was in my choice of America as such a place,” he wrote in an unpublished essay just after becoming a citizen. “On every side I hear men and women expressing their opinion on candidates for office and the issues of the day without fear of consequences.”
The beauty of America, he said, was that this tolerance of each person’s ideas existed without the “brute force and fear” that had arisen in Europe. “From what I have seen of Americans, I think that life would not be worth living to them without this freedom of self expression.”26 The depth of his appreciation for America’s core value would help explain Einstein’s cold public anger and dissent when, during the McCarthy era a few years later, the nation lapsed into a period marked by the intimidation of those with unpopular views.
More than two years after Einstein and his colleagues had urged attention to the possibility of building atomic weapons, the United States launched the supersecret Manhattan Project. It happened on December 6, 1941, which turned out to be, fittingly enough, the day before Japan launched its attack on Pearl Harbor that brought the nation into the war.
Because so many fellow physicists, such as Wigner, Szilard, Oppenheimer, and Teller, had disappeared to obscure towns, Einstein was able to surmise that the bomb-making work he had recommended was now proceeding with greater urgency. But he was not asked to join the Manhattan Project, nor was he officially told about it.
There were many reasons he was not secretly summoned to places like Los Alamos or Oak Ridge. He was not a nuclear physicist or a practicing expert in the scientific issues at hand. He was, as noted, considered by some a security risk. And even though he had put aside his pacifist sentiments, he never expressed any desire or made any requests to enlist in the endeavor.
He was, however, offered a bit part that December. Vannevar Bush, the director of the Office of Scientific Research and Development, which oversaw the Manhattan Project, contacted Einstein through the man who had succeeded Flexner as the head of the Institute for Advanced Study in Princeton, Frank Aydelotte, and asked for his help on a problem involving the separation of isotopes that shared chemical traits. Einstein was happy to comply. Drawing on his old expertise in osmosis and diffusion, he worked on a process of gaseous diffusion in which uranium was converted into a gas and forced through filters. To preserve secrecy, he was not even allowed to have Helen Dukas or anyone else type up his work, so he sent it back in his careful handwriting.
“Einstein was very much interested in your problem, has worked on it for a couple of days and produced the solution, which I enclose,” Aydelotte wrote Bush. “Einstein asks me to say that if there are other angles of the problem that you want him to develop or if you wish any parts of this amplified, you need only let him know and he will do anything in his power. I very much hope that you will make use of him in any way that occurs to you, because I know how deep is his satisfaction at doing anything which might be useful in the national effort.” As an afterthought, Aydelotte added, “I hope you can read his handwriting.”27
The scientists who received Einstein’s paper were impressed, and they discussed it with Vannevar Bush. But in order for Einstein to be more useful, they said, he should be given more information about how the isotope separation fit in with other parts of the bomb-making challenge.
Bush refused. He knew that Einstein would have trouble getting a security clearance. “I do not feel that I ought to take him into confidence on the subject to the extent of showing just where this thing fits into the defense picture,” Bush wrote Aydelotte. “I wish very much that I could place the whole thing before him and take him fully into confidence, but this is utterly impossible in view of the attitude of people here in Washington who have studied his whole history.”28
