In 1943, at 38 years old and with no previous administrative experience, physicist J. Robert Oppenheimer accepted responsibility for a national security mission of unprecedented scale.
His charge, handed down by Manhattan Project director General Leslie Groves, was to lead a team of the world’s foremost scientific minds in developing the first nuclear weapon. Under Oppenheimer’s leadership, more than 6,000 scientists, engineers, and other personnel lived and worked at a top-secret lab in Los Alamos, New Mexico, and completed their task in only 27 months. Weeks later, they delivered the world’s first two nuclear bombs to the U.S. military. World War II ended shortly thereafter.
Long before joining the Manhattan Project, Oppenheimer had a personal connection to northern New Mexico. Prone to illness in his youth, an 18-year-old Oppenheimer spent a restorative and formative summer at Los Piños ranch near Santa Fe. He returned often to the area in adulthood, even as a busy academic teaching physics at the University of California, Berkeley and the California Institute of Technology.
The fall of 1942 found Oppenheimer back in New Mexico touring a potential site—Jemez Springs—for Project Y, the wartime codename for what would eventually become Los Alamos National Laboratory. Both Oppenheimer and Groves found Jemez Springs unsuitable, and Oppenheimer proposed a nearby alternative: Los Alamos, which he had once visited during a horse-packing trip. There, a few homesteads and a boys’ boarding school sat on an isolated, nearly inaccessible plateau—the perfect location for a secret lab.
Within a few months, the federal government had acquired 50,000 acres of land, including the boy’s school, which rushed to graduate its oldest students by January 1943. That spring, crews broke ground on the additional buildings necessary for a full-scale nuclear research laboratory.
Even before the construction dust settled, in March 1943, Oppenheimer and Groves began assembling a team of the world’s brightest scientific minds. Oppenheimer, of course, was brilliant himself. An accomplished theoretical physicist, intellectual jack-of-all-trades, and a deep thinker well-read in Eastern philosophy, Oppenheimer was a guiding force in asking and answering the research questions that led to groundbreaking innovations at the Lab.
Though he had no shortage of expert advisors and team leaders, including more than a dozen current or future Nobel laureates, Oppenheimer bore the responsibility of making critical scientific and personnel decisions to keep the Lab on track and on schedule. Many who worked with Oppenheimer said that there was no other man for the job. His profound understanding of both nuclear physics and human nature made Oppenheimer a natural leader of his technical staff and an able keeper of the specialized research underway across the Lab’s four divisions.
Oppenheimer’s counsel continued to pave the way as Los Alamos reached a crossroads in mid-1944. Atomic bomb design had been progressing along two lines: a gun-type uranium device called Little Boy and a gun-type plutonium device called Thin Man. After a series of failed experiments that were attributed to an incompatibility between the gun-type mechanism and plutonium fuel, Oppenheimer gave the order to abandon the Thin Man design. He then raised two new divisions divisions—Explosives and Weapons Physics—to design and build a complex and unproven imploding weapon. On July 20, 1944, he declared at an administrative board meeting that “all possible priority should be given to the implosion program.”
The decision paid off. The Gadget—an implosion device with a plutonium core—was detonated on July 16, 1945, at the Trinity site in southern New Mexico. The successful design—patented by Oppenheimer—was replicated as Fat Man, one of two atomic bombs supplied to the U.S. military in August 1945.
The Little Boy and Fat Man atomic bombs were released above Japan on August 6 and 9, respectively. Japan surrendered shortly thereafter, and World War II officially ended on September 2, 1945.
The Manhattan Project was complete. On October 16, 1945, the Army-Navy E Award for excellence in war production was bestowed upon Oppenheimer and the scientists, engineers, military personnel, and others at the Lab whose patriotism “helped our country along the road to victory.” On the day of this capstone event, Oppenheimer announced his resignation.
He would go on to serve in important advisory roles as the United States debated the future of nuclear research and the wartime lab at Los Alamos. ★