Oppenheimer: What Happened To The Physicist After The Manhattan Project?

Christopher Nolan's latest film, "Oppenheimer," is a biographical thriller dedicated to the life of the theoretical physicist Julius Robert Oppenheimer (Cillian Murphy). The film was inspired by the biographical novel "American Prometheus," which chronicles Oppenheimer's life before, during, and after World War II.

Credited as the "father of the atomic bomb," history buffs know Oppenheimer began leading the infamous Manhattan Project in 1942, and over the next few years, he and his team utilized nuclear fission reactions to create a bomb of unprecedented strength. Most people know the story from there: how the atomic bomb was used on Hiroshima and Nagasaki to end World War II, and how hundreds of thousands of civilians lost their lives to Oppenheimer's creation.

While these facts remain common knowledge to this day, most people are unaware of what actually happened to Oppenheimer after the Manhattan Project shut its doors in 1947. Following the war, Oppenheimer was made director of the Institute for Advanced Study at Princeton, and named to the advisory board for the Atomic Energy Commission. Despite shifting his focus from military applications to energy production, Oppenheimer was stripped of his United States security clearance in 1954 due to his alleged ties to the Soviet Union. Oppenheimer would spend the rest of his life studying physics and lecturing across the world, and remained a colossal figure in the scientific community despite his controversial expulsion from the United States government.

While J. Robert Oppenheimer's later life was certainly full of ups and downs (particularly his involvement with the second Red Scare), perhaps the most fascinating aspect of his post-war career was his pacifist work.

Oppenheimer's opposition to nuclear war reportedly began just eleven days after his bomb leveled Hiroshima, when he wrote to the United States government and pushed for nuclear disarmament. A few months later, Oppenheimer met directly with Harry S. Truman and reportedly told the president that he had "blood on his hands," which in turn caused Truman to call Oppenheimer a "cry-baby scientist" and ban him from his office. Oppenheimer would go on to lobby against the development and use of hydrogen bombs –- a move that made him even more unpopular within the U.S. government and possibly influenced the investigation into his communist leanings.

Despite all of Oppenheimer's hand-wringing about the threat of nuclear weapons, throughout his life he constantly defended the use of atomic bombs against Japan. In an interview with PBS, historian Alex Wellerstein says Oppenheimer believed the bombs were necessary to end the war but should never be used again, and that he believed his responsibility to the world outweighed the moral dilemma of the bomb. It's clear Oppenheimer was an immensely complex figure whose later life was rife with conflict, and his story provides more than enough content for Christopher Nolan's latest cinematic epic.