Harold C. Urey: Science, Religion, and Cold War Chemistry

After helping create the atom bomb as part of the Manhattan Project, Harold Urey focused on uncovering the age and origins of Earth and the solar system. In this 1951 photo Urey inspects a 'fossilized thermometer' of belemnite (a prehistoric squid-shaped creature). Urey used information from these fossils to estimate the temperature of oceans from as far back as 100 million years. (USC Digital Library)

After helping create the atom bomb as part of the Manhattan Project, Harold Urey focused on uncovering the age and origins of Earth and the solar system. In this 1951 photo Urey inspects a 'fossilized thermometer' of belemnite (a prehistoric squid-shaped creature). Urey used information from these fossils to estimate the temperature of oceans from as far back as 100 million years. (USC Digital Library)

The end of World War II was a time of great relief for Americans. With the economic boom that followed on its heels, it was also a time of great optimism. As the powers of Europe tended their wounds, an “American Century” appeared imminent.

Yet for many scientists—especially those who had contributed their talents and expertise to the development of America’s atomic bomb—the end of this war and the lead-up to the Cold War was also a time of great anxiety. The existence of the bomb led them to one horribly obvious conclusion: any future war could bring the end of the world as they knew it, perhaps even the annihilation of all human civilization.

Harold C. Urey, wartime director of the Manhattan Project’s uranium isotope–separation program at Columbia University, was one of the most anxious scientists in America. “I’m a frightened man,” he proclaimed in the pages of Collier’s only months after the bombings of Hiroshima and Nagasaki. “I write this to frighten you,” he added. “All the scientists I know are frightened—frightened for their lives—and frightened for your life.”

But how to survive the Atomic Age? This question preoccupied Urey for the rest of his life. His prescription for survival shifted and evolved throughout the Cold War, influenced by changes in American politics and culture. No less important in shaping Urey’s position was a very personal and occasionally uneasy balance between his religious upbringing and his scientific skepticism.

These outside forces transformed Urey’s public position on the atomic question, leading him from advocating for world governance of atomic weapons to promoting an extreme nuclear imbalance in favor of the United States and its allies. Urey also transformed his laboratory during the Cold War, introducing a new focus on the history of the earth and solar system and the origins of life.

Beginning in the 1950s Urey’s inner struggle led him to publicly call for a new synthesis of science and religion. Instead of the miraculous, he offered a grand view of the universe provided by science. Such an awe-inspiring vision, he believed, would help maintain the traditional religious morals required to prevent the use of atomic weapons.

Atomic Trauma

In the wake of Hiroshima and Nagasaki atomic scientists found themselves thrust into the public eye. Some, like theoretical physicist J. Robert Oppenheimer, head of the Manhattan Project and “father” of the atomic bomb, became official advisers to the government on atomic science. Others turned their fears to collective action, forming organizations whose missions were twofold: educate policy makers and the public about the danger of atomic weapons and promote the development of peaceful atomic research.

Urey was already a celebrity, having won the Nobel Prize in Chemistry in 1934 for the discovery of deuterium (a heavy isotope of hydrogen with a mass of 2). In their efforts to control the bomb Urey and a handful of other eminent scientists founded the Emergency Committee of Atomic Scientists. Here Urey acted as vice chairman under his fellow Nobelist and scientific hero, Albert Einstein. As one of the committee’s most public representatives Urey spent a great deal of his postwar time traveling and speaking to the public.

In the wake of the bomb this public work seemed urgent. Urey told the New Yorker in December 1945 that he had “dropped everything” related to his own research program, setting it aside until the world had received the message of fear and caution given by Urey and his colleagues. These weapons were so destructive, they argued, that the only way to keep the world safe was to institute a world government to monitor and control their further development.

In truth Urey found it difficult to even think about returning to his scientific work. “I know the bomb can destroy everything we hold valuable, and I get a sense of fear that disturbs me in my work,” he told reporters. “I feel better if I try to do something about it.”

The bomb wasn’t the only reason Urey found it difficult to return to work. He seemed anxious to distance himself physically and mentally from everything connected to his war work—work to which his earlier research in isotope separation bore too much resemblance. Urey had in fact been traumatized by his war work long before the dropping of the first bomb. The pressures of meeting the army’s timeline for the design and fabrication of a uranium isotope–separation facility, combined with clashes with military managers and his own scientific technical staff, had brought him close to a nervous breakdown.

While his crusade for world governance of atomic weapons initially may have afforded Urey an escape from his war trauma, this diversion soon delivered its own stresses. As Cold War tensions escalated and anti-Communist hysteria grew, any thoughts of the United States sacrificing any of its sovereignty or military strength became both unrealistic and politically risky. Those organizations and individuals who advocated for world government suffered for it.

By early 1947 Urey was all but worn down. The breakdown of negotiations between the United States and the Soviet Union over control of atomic weapons pushed Urey into a more hawkish position: the United States must maintain nuclear superiority to prevent the Soviet Union from starting a nuclear war. Meanwhile, Urey’s one-world idealism—which often went beyond the control of atomic weapons—brought attacks by the House Committee on Un-American Activities as well as an investigation by the FBI. Urey wrote to Einstein that the stress had left him exhausted but unable to sleep and that his doctors had ordered him to avoid outside activities. He even joked to the press that he was thinking of disconnecting his phone and changing his name.