Who is Oppenheimer?

New scientific findings have the power to pique interest, shed light on mysteries, and even change the world. What transpires, then, if a scientist later learns to regret the information he has unleashed?

The upcoming movie Oppenheimer, which tells the story of American scientist J. Robert Oppenheimer's moonshot mission to create an atomic bomb in a top-secret facility in the New Mexico desert—and his lifelong concerns about the nuclear era he usher in—has this as its core theme.

Was the great physicist truly sorry for inventing the nuclear bomb? The science underlying the bomb is as convoluted as the truth. Here is how Oppenheimer developed the atomic bomb and raised doubts about it.

Young prodigy to Manhattan Project

Julius Robert Oppenheimer was the son of German Jewish immigrants who became wealthy through the textile importing business and was born in New York City in 1904. After only three years of study, he received his summa cum laude degree from Harvard University. He subsequently pursued further studies in theoretical physics at Cambridge University and the University of Göttingen in Germany, where he received his doctorate at the age of 23.

Soon, "Oppie" the young physicist was rubbing elbows with the best minds of his time. His academic work expanded quantum theory and made numerous predictions, ranging from the neutron to the black hole. He was also a voracious learner outside of the sciences, studying religion, acquiring Sanskrit, and supporting several progressive causes.

Oppenheimer was requested to take part in the top-secret Manhattan Project, whose goal was to create an atomic weapon, when the United States allied with the Allies in 1941. Oppenheimer's supervisors were impressed by his broad knowledge, ambition, and capacity to collaborate with and motivate other scientists as he worked to understand what would need to occur to start and maintain the kind of neutron-chain reaction required to produce a nuclear explosion. The American Army asked Oppenheimer to lead the covert facility where the bomb would be tested in 1942.

Los Alamos and the Trinity experiment

Oppenheimer, who adored the American Southwest and had a ranch in New Mexico, recommended the location of the Los Alamos Ranch School, a private boys' school close to Santa Fe, as Army officials looked into suitable locations for such a lab. Soon, he was in charge of hundreds, then thousands, of employees at the Los Alamos Laboratory.

Not only did Oppenheimer gather a team of the brightest scientific brains of his era, but he also motivated, organized, and prodded them to succeed. Physicist Victor Weisskopf subsequently observed, "He was intellectually and even physically present at each decisive step." This presence led to "a unique atmosphere of enthusiasm and challenge" and a series of scientific breakthroughs that led to the creation of the first nuclear weapon in history.

Oppenheimer and colleagues assembled on July 16, 1945, at the Trinity test site south of Los Alamos for the first nuclear explosion attempt ever made. The scientists were under pressure because they understood how the bomb they had dubbed "Gadget" would affect the course of history.

However, they also thought that it might put an end to World War II. Although the war in Europe was over, U.S. leaders worried that the worst part of the conflict—attacks against Japan—was still to come. The nation hoped that by threatening to deploy the new weapon, it could compel Japan to submit instead.

The covert test was successful. The incident, according to Oppenheimer, reminded him of a passage from the Hindu Bhagavad Gita: "Vishnu is trying to persuade the prince that he should do his duty, and to impress him, puts on his multi-armed form and declares "Now I am become Death, the destroyer of worlds." Oppenheimer recalled this in a 1965 interview. In some way or another, I believe we all thought that.

The moral repercussions of bombing Japan

The United States exploded two of the bombs Oppenheimer had assisted in developing over Hiroshima and Nagasaki on August 6 and August 9, 1945. The explosions are estimated to have killed at least 110,000 people and destroyed both cities on a magnitude that has never been seen before or since.

Oppenheimer was a member of the scientific panel that advised the War Department to use the bomb against Japan as soon as possible. There is ongoing historical controversy over whether the administration heeded scientists' recommendations that the bomb be used only against military targets or even publicly tested beforehand in an effort to compel Japan to submit.

Oppenheimer was applauded by a group of his scientific peers the night after the Hiroshima explosion and said his only regret was that the bomb hadn't been developed in time to be used against Germany.

Even while they were ecstatic about their success, the scientists were horrified by the deaths of innocent bystanders in the strike and worried that the weapons' potential use might encourage rather than prevent future battles. In a letter to the Secretary of War a few weeks after the bombing, Oppenheimer cautioned that "the protection of this nation...cannot lie wholly or even principally in its scientific or technical prowess. It can only be founded on eliminating the possibility of future battles.

Oppenheimer nevertheless defended the Manhattan Project and the bomb he was tasked with creating, claiming that it was essential to fully grasp the potential of nuclear physics.

Opposing the hydrogen bomb

Nevertheless, Oppenheimer devoted a large portion of his life to promoting nuclear deterrence after the war, strongly criticizing American efforts to create a more potent hydrogen bomb when the U.S.S.R. made progress with its own bomb. Oppenheimer recommended that the United States should focus on alternative applications of nuclear technology, such as power generation, and think about utilizing nuclear weapons only in tactical situations.

Due of this, he gained political opponents and was targeted by the Red Scare, a Cold War-era anti-Communist frenzy in American politics. The Atomic Energy Commission canceled his security clearance following an investigation into his alleged Communist leaning in 1954. Only in 2022, when government officials looked again at Oppenheimer's case and discovered that the inquiry had been illegal and defective, was the decision reversed.

According to historian Alex Wellerstein for the PBS NewsHour, "He doesn't slot into easy categories of pro-nuclear, anti-nuclear, or anything like that." He is a tough character.

Oppenheimer founded the World Academy of Arts and Sciences and lectured on science and ethics until his death in 1967, never returning to the government service. Despite having contributed to the development of the "necessary" weapon that ended a conflict, leveled two cities, and brought about a perilous new era, he spent the rest of his life advocating against the spread of nuclear weapons.

"The physicists have known sin; this is a knowledge which they cannot lose," he observed in 1950, "in some crude sense which no vulgarity, no humor, no overstatement can quite extinguish."