Nearly 70 years ago, the man who helped the United States develop the world’s first nuclear bombs was accused of being a communist. Finally, his name has been cleared.
July 19, 2023
In the late spring of 1954, the Atomic Energy Commission (AEC) held a closed-door hearing to decide the fate of J. Robert Oppenheimer’s security clearance. Oppenheimer, a physicist, had led the scientific effort to build the world’s first nuclear weapons that helped end World War II, and now, nine years later, his loyalty to the country was being questioned.
The four-week hearing became a national spectacle. Politicians, high-ranking military officials, and some of the world’s most renowned physicists testified both for and against the revocation of Oppenheimer’s security clearance.
“We have an A-bomb” because of Oppenheimer’s work, physicist Isidor Rabi told commissioners as he vouched for his friend and colleague. “What more do you want, mermaids?”
In the end, the AEC ruled to revoke Oppenheimer’s clearance, which denied him all access to the nation’s atomic secrets—science that he played a major part in developing.
“My train wreck,” is how Oppenheimer later referred to the hearing, and his close friends say he was never the same.
However, in December 2022, the Department of Energy (DOE, the successor to the AEC) nullified the AEC’s earlier ruling, calling the entire hearing flawed. “As time has passed, more evidence has come to light of the bias and unfairness of the process that Dr. Oppenheimer was subjected to,” Energy Secretary Jennifer M. Granholm said in a statement, “while the evidence of his loyalty and love of country have only been further affirmed.”
Provided the context now available, it is widely believed that the hearings against Oppenheimer arose from personal grievances and insider politics. Clearing his name, however, was a much more public struggle, one that generations of Los Alamos National Laboratory scientists, and even directors, took on.
A Soviet spy?
After World War II, Oppenheimer became chairman of the AEC’s General Advisory Committee, a post that solidified him as America’s leading mind on atomic weapons. At the time Oppenheimer led the committee, one major priority was how the nation should proceed after, in 1949, the Soviet Union successfully detonated its own atomic bomb.
Almost immediately, the AEC called for a series of planning sessions. During these sessions, Oppenheimer sometimes displayed little patience toward people who spoke on topics they didn’t comprehend, and at one AEC session before Congress, Oppenheimer clashed with fellow AEC commissioner Lewis Strauss, a former naval officer. Strauss thought the United States should not export radioactive isotopes to foreign countries because the isotopes held special military value.
Radioactive isotopes are indeed necessary for nuclear weapons, but they also have myriad peaceful uses, which is why Oppenheimer believed that the United States should share this technology with other countries. During the session, Oppenheimer offered a condescending remark to Stauss’ recommendation: “My own rating of the importance of isotopes,” Oppenheimer said, “is that they are far less important than electronic devices, but far more important than, let us say, vitamins.”
Strauss was humiliated, publicly. It was the start of a rivalry that would end in Oppenheimer losing his security clearance.
The greatest contention between Oppenheimer and Strauss was whether to build a hydrogen bomb, a potentially smaller but more powerful weapon than the first-generation atomic bombs developed during the Manhattan Project. Strauss, alongside physicists Edward Teller and Stanislaw Ulam, both of whom Oppenheimer had worked with at Los Alamos, believed the United States needed the hydrogen bomb to gain technological advantage over the Soviet Union. Oppenheimer was against such a device, which many assumed to mean he was anti-American.
A hydrogen bomb would require large quantities of the rare hydrogen isotope tritium. This element is made by irradiating lithium in nuclear reactors that, in 1949, would have otherwise been devoted to breeding plutonium for atomic bombs. Oppenheimer felt the nation faced a binary choice: build more of something the country knew it was capable of building, his atomic bomb, or risk precious space in nuclear reactors to breed tritium for a still-theoretical hydrogen bomb.
By 1953, in the middle of the McCarthy “Red Scare” era, Strauss was appointed chairman of the AEC. Strauss seemed to have never let go of Oppenheimer’s comments, or his stance against the hydrogen bomb. As AEC chairman, Strauss called for an investigation into Oppenheimer, claiming there was evidence the physicist was a Soviet spy.
In previous decades, especially during his time at the University of California, Berkeley, Oppenheimer had associated with many communist sympathizers—his brother, a former fiancée, and close friends, to name a few. On a Manhattan Project security questionnaire, Oppenheimer had once joked that while he’d never been a communist, he’d “probably belonged to every communist-front organization on the West Coast.”
In December 1953, Strauss sent a letter to Oppenheimer saying his security clearance was suspended pending an investigation into his loyalty to the nation. Give up his clearance and resign from the AEC, the letter demanded, or appear before an investigatory board. Oppenheimer chose the latter.
The hearing took place in Washington, D.C., near the White House. Oppenheimer’s defense lawyer was never granted the clearance to review classified documents, however, so the team was cut off from much of the prosecution’s evidence. Strauss acted as chief appellate judge. Secretly, Strauss had also contacted the FBI, which illegally wiretapped Oppenheimer’s phone communications with his attorney.
At the hearing, which began on April 12, 1954, two of the most damning testimonies came from long-time colleagues. One was General Leslie Groves, who’d handpicked Oppenheimer to lead the Manhattan Project. Groves defended the physicist at the hearing, but the general also said that he would probably not be allowed to clear Oppenheimer using the updated security clearance regulations introduced that year. Teller, who would go on to develop the hydrogen bomb, questioned Oppenheimer’s character, his methods, and his hesitancy to develop a hydrogen bomb. “I would feel personally more secure,” Teller testified, “if public matters would rest in other hands.” For this, the Los Alamos scientific community would later shun Teller.
At the end of the four-week hearing, the AEC board voted two-to-one to revoke Oppenheimer’s clearance. The board found no evidence to support Strauss’s claim that Oppenheimer was a spy, but noted that he had many past ties to communists, as Oppenheimer had already revealed. In its decision, the board also emphasized Oppenheimer’s resistance to the hydrogen bomb, writing that his position “had an adverse effect on recruitment of scientists and the progress of the scientific effort.”
Later that year, the AEC published a redacted transcript of the hearing, called In the Matter of J. Robert Oppenheimer, which revealed to the public the blatant unfairness of the hearing. (In 2014, the U.S. government released previously classified information on the hearing, and many of the details upheld Oppenheimer’s loyalty to the nation.)
Correcting a historical wrong
Meanwhile, back in Los Alamos, Oppenheimer's colleagues at the Lab fought to restore their former director’s good name. Led by physicist Fred Ribe, 494 scientists risked their own careers when they signed a petition and sent it to President Dwight Eisenhower and the AEC in 1954.
“The nature of the argument by which the majority of the board nevertheless concludes that he is a security risk is alarming,” Ribe wrote. “…we are apprehensive that this poorly founded decision … will make it increasingly difficult to obtain adequate scientific talent in our defense laboratories.”
The petition never delivered the desired effect.
In the years after his security clearance was revoked, Oppenheimer retired from public service, though he still contributed heavily to the scientific community. He helped found the World Academy of Arts and Sciences in 1960, and he continued to lecture and write about physics. Oppenheimer, a constant smoker, died of throat cancer in 1967.
Over the decades, the scientific community at the Lab tried repeatedly to correct the historical mistake that left a black mark on Oppenheimer’s name. There were small moments of victory, like in 2004 when the U.S. Senate—on the 100th anniversary of Oppenheimer’s birth—passed a resolution to recognize “the loyal service to America of Dr. J. Robert Oppenheimer,” but the smirch upon his security clearance remained.
Then in April 2022, members of the Lab tried once more to nullify the AEC’s decision.
Laboratory Director Thom Mason and eight former Los Alamos directors signed a letter and delivered the note to Secretary of Energy Granholm, urging DOE to nullify the AEC’s decision as a “historically appropriate remedy” to what they saw as an egregious mistake. In December 2022, Granholm made the DOE’s decision known.
“As a successor agency to the Atomic Energy Commission, the Department of Energy has been entrusted with the responsibility to correct the historical record and honor Dr. Oppenheimer’s profound contributions to our national defense and the scientific enterprise at large,” Granholm said in a statement. “Today, I am pleased to announce the Department of Energy has vacated the Atomic Energy Commission’s 1954 decision In the Matter of J. Robert Oppenheimer.”
The decision was roundly hailed—by scientists, historians, and the media—as an appropriate gesture to clear the name of a man who dedicated his career to the nation’s security.
“Although this brings no peace to Dr. Oppenheimer, who died long ago, it brings needed perspective to the real truth of his legacy, integrity, and moral courage,” Mason said of the decision. “It also sends a message that while the U.S. government takes security seriously and expects truthfulness, it must reciprocate with a fair analysis and principled decisions.” ★