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Reviewed by:
  • Restricted Data: The History of Nuclear Secrecy in the United States by Alex Wellerstein
  • Robert Jervis
Alex Wellerstein, Restricted Data: The History of Nuclear Secrecy in the United States. Chicago: University of Chicago Press, 2021. 549 pp. $35.00.

Having worked with classified information on and off for most of my adult life and spent more than a decade chairing the Historical Review Panel (HRP) of the U.S. Central Intelligence Agency (CIA), I am painfully familiar with the classification and declassification system. Despite my objections to several aspects of this system, I have come to take most of it for granted. As Alex Wellerstein says, by the mid-1960s the secrecy regime "had become so embedded in the fabric of American bureaucracy, and the American security mindset, that it is difficult to imagine anything different at this point" (p. 287). For me, therefore, it was eye-opening to read Wellerstein's deeply researched and thoughtful account of the evolution of the classification of information related to nuclear weapons, labeled Restricted Data (RD), as in the title of the book. Of course this is just one part of the total secrecy universe, but looking only at this one part allows Wellerstein to go into great and fascinating detail, bringing out the disputes, tensions, and paradoxes of what he calls the security regime in his chosen area. Anyone interested in the Cold War dilemmas of secrecy will be riveted and will benefit from reading this book.

One of the many surprises is that, led by the liberal gadfly Leo Szilard, restrictions started as self-censorship among nuclear scientists years before the establishment of the Manhattan Project. In July 1941, U.S. scientists learned about the British MAUD report showing that a nuclear bomb could be built out of a reasonable amount of uranium 235, a document that was also provided to the USSR by the spy John Cairncross. This was the first consequential breach of security concerning these weapons (surprisingly not mentioned by Wellerstein), and, like many subsequent ones, it was discovered only years later, contributing to an overconfidence in the system.

Secrecy became much stricter and more institutionalized once the Manhattan Project was underway with General Leslie Groves in charge. But even though Groves was deeply concerned about safeguarding the program against German espionage, he was less worried about information reaching the USSR than he was about keeping the secret from the U.S. public and, especially, Congress, which might interfere. The tension between secrecy and democracy was present from the start.

I have used the term "the secret," but one of Wellerstein's themes is that, with few exceptions, the knowledge needed to build fission bombs (and later thermonuclear bombs) was not secret. Many of the watchdogs, especially in Congress after 1945, [End Page 159] harped on keeping others from knowing "the secret," but it was less the nuclear physics than the technological methods of producing fissile material and the industrial and engineering know-how involved that was crucial. Although the initial Soviet program was significantly expedited by the spies at Los Alamos, Oak Ridge, and other facilities, and although the Teller-Ulam configuration to ignite a fusion bomb was a real secret for some years, by the time Howard Moreland published the Teller-Ulam configuration in The Progressive magazine in 1979 most of the information was widely known. Wellerstein convincingly argues that the large majority of early critics of secrecy like J. Robert Oppenheimer were correct to argue that an alternative regime that focused on controlling the material that was necessary to build the weapons would have been more effective than trying to keep enormous amounts of information classified.

Another of Wellerstein's themes is that there is a tension or even a contradiction not only between secrecy and democracy but also between secrecy and the science that created the secrets. "The postwar system attempted to have everything both ways. Science needed to be open, but the bomb needed to be contained" (p. 176). Although competition among scientists sets some limits on openness, science is inherently a collective enterprise, and many in the national security establishment joined with scientists in criticizing strict secrecy on the grounds...