Born secret – the heavy burden of bomb physics

Project Los Alamos main gate

Los Alamos in New Mexico, a major nuclear weapons site during World War II.Credit: John Dambik / Alamy

Limited Data: The History of Nuclear Secret in the United States Alex Wellerstein Univ. Chicago Press (2021)

In March 1950, an official of the Atomic Energy Commission – then the custodian of US nuclear secrets – oversaw the burning of thousands of copies of the magazine. American scientist. The dispute? They contained information so secret that its publication could endanger the free world.

Several statements in an article about the hydrogen bomb raised red flags with government officials, although they were all previously reported publicly. The government’s concern was not with what it said, but with who said it. Physicist Hans Bethe, who wrote the article, was head of the theoretical division at the Los Alamos lab in New Mexico during Project Manhattan, the top-secret World War II program that led to the atomic bomb.

The burning magazine is one of several arresting episodes told in the pioneering book Limited Data. Alex Wellerstein, a historian of science, chronicles the twisted path of nuclear secrecy from the early days of nuclear separation research, through the Manhattan Project, into the Cold War and beyond.

The best writers pretend the familiar foreign, difficult assumptions about things we consider to be granted. It may seem obvious that building the most powerful weapon in the world, a device that could end human civilization, requires extreme secrecy. However Wellerstein peels the layers of the nuclear onion to reveal a rich debate about what should be hidden and why. The restrictions often had dubious benefits for national security, but undoubtedly hampered research on nuclear energy and frustrated scientists who thought the free exchange of ideas was key to progress.

The book extracts its title from a “new and unusually expansive legal category that applied only to nuclear secrets.” This label, “limited data,” was created in the United States in 1946. It designates all knowledge related to the creation of nuclear weapons, from nuclear fusion to the production of fissile material, as a “born secret” regardless of where it originated. – a discovery in a private industrial laboratory, university or someone’s warehouse. This is thus a story about “the annoying problem raised by fears of dangerous knowledge in a nation where information is anything but easy to master,” Wellerstein writes.

The name created obstacles for researchers who thought that ideas they developed without a link to secret research belonged to them. Wellerstein tells in fascinating detail the history of KMS Industries in Ann Arbor, Michigan, which attempted to process laser-driven fusion in the 1960s and 1970s, basing its efforts on the research of physicist Keith Brueckner. The company faced legal threats, patents blocked and faced growing debt as it opposed the government for the right to continue its work.

Nuclear misunderstandings

In the minds of many, even today, violating a nuclear secret is about giving some specific “ultimate” knowledge of how a nuclear weapon works, as happened when German-born physicist Klaus Fuchs handed over details about the U.S. atomic bomb to the Soviet Union. In movies, and sometimes in real life, spies deliver projects that reportedly enable a country or group to build their own nuclear weapons. Wellerstein shows that this concept is often wrong and has been at the heart of debates for decades.

Wellerstein traces the history of nuclear secrecy from the early days of physical exploration. In the late 1930s, scientists, especially Hungarian physicist Leo Szilard, who first theorized the nuclear chain reaction, advocated self-censorship, recognizing the possibility of a weapon that could change the course of World War II. After the Manhattan Project began in 1942, that self-censorship was transformed under the strict fist of its director, General Leslie Groves, into a formal regime of secrecy. (Groves pressed unsuccessfully to intern Szilard for the duration of the war.)

There were cracks in the secrecy facade early on, and attempts to reinforce it led to absurdity. When an Ohio reporter visited New Mexico and wrote in March 1944 about rumors of a secret city that was involved in “huge explosions,” Groves tried to militarize him. “This failed,” Wellerstein dies, “because the reporter was sixty years old.”

Wellerstein’s book is compelling and frightening because it confronts the reader with the confusing questions faced by scientists and government officials, trying to decide what information to retain. It might seem absurd to burn magazines containing familiar information, but if that information, presented authoritatively, even risked helping an enemy nation build weapons, wouldn’t it be better to err cautiously?

The counter-argument was made prudently in the 1970s by nuclear physicist Ted Taylor, addressing a hypothetical terrorist group trying to acquire a nuclear weapon. “Get rid of any complexity altogether,” he said, pointing out that the existence of fissile material, rather than knowledge of how to do it, was the real danger. “Try to see what is the simplest way to do something that could upset the World Trade Center.” As we learned decades later, no nuclear weapon was needed to accomplish this.

Wellerstein’s work also raises some interesting questions about modern secrecy beyond nuclear weapons research, with implications for fields from cybersecurity to political studies. He points out, for example, that a U.S. Navy spy analyst was accused of espionage in the 1980s and sentenced to two years in prison for giving satellite photos of Soviet nuclear aircraft to a British defense magazine. (The analyst, unnamed in the book, is Samuel Morison, later pardoned by President William J. Clinton.)

Fast forward about 40 years, and Reality Winner, a veteran Air Force in its twenties, was sentenced to 5 years in prison for leaking a document showing that Russia hacked into voter registration systems in an attempt to thwart the 2016 U.S. presidential election. Her outburst was illegal, but revealing something that was talked about at night on cable news seems hardly as serious as revealing secrets about the nuclear weapons race.

How has the modern state security state reached a point where the very act of leaking information is considered more threatening to national security than the damage caused by discovery? The answer to that needs another book, but Wellerstein has prepared the basis for anyone who chooses to investigate that dark corner.