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Oppenheimer and Einstein

'Destroyer of Worlds' J. Robert Oppenheimer and the Manhattan Project

Robert Oppenheimer conversing with Albert Einstein | Pubic Domain

‘We knew the world would not be the same. A few people laughed, a few people cried. Most people were silent. I remembered the line from the Hindu scripture, the Bhagavad Gita; Vishnu is trying to persuade the prince that he should do his duty and, to impress him, takes on his multi-armed form and says, "Now I am become Death, the destroyer of worlds." I suppose we all thought that, one way or another.’ - J. Robert Oppenheimer, 1965.

An unlikely leader

He was a surprising choice to lead a top-secret government weapons program. The stick-thin, chain-smoking physicist with a penchant for leftwing politics and a very unscientific interest in mysticism, J. Robert Oppenheimer was first attached to what became known as the ‘Manhattan Project’ shortly after President Franklin D. Roosevelt approved a program to develop an atomic bomb, two months before the USA entered the Second World War in September 1941.

Part of a group of American and European scientists tasked with working out the sequence of events that would lead to the successful detonation of an atomic weapon, Oppenheimer impressed with the way he threw himself into the tasks with relish.

When it came time to set up the Manhattan Project in June 1942, its leader, Brigadier General Leslie R. Groves of the United States Army, picked Oppenheimer to be the head of the project’s secret weapons laboratory. Many were surprised. Oppenheimer had no previous history of leading large projects. His lack of a Nobel Prize was also concerning - the project would be drawing together some of the greatest American and European minds. Would they be happy working under a man who had not been recognised with the top prize in his field?

Cometh the hour, cometh the man

As it turned out, Oppenheimer was the perfect man for the job. Groves had correctly identified traits in Oppenheimer that many others had missed - a mind that could grasp the complexities involved in creating an atomic bomb, a huge breadth of knowledge and a singular drive to achieve the project’s goal. Oppenheimer was appointed lead scientist in September 1942 by Groves. As the Brigadier predicted, he would doggedly see the project through to its spectacularly successful end.

Groves and Oppenheimer quickly came to the conclusion that they needed a centralised, secret location to house the facility that would research, build and test the bomb. Having a fondness for the heat and isolation of the New Mexico desert after convalescing there from a bout of TB before the war, Oppenheimer suggested buying a boy’s private school near the city of Santa Fe. Groves agreed, and the Los Alamos Ranch School became the Los Alamos Laboratory, which would soon become a sprawling complex in the desert that would grow from a handful of scientists in early 1943 to over 6,000 in 1945.

The Manhattan Project

The aim of the project was to harness the power of nuclear fission to create a weapon of unprecedented destructive capabilities. Fears that the Germans were also aiming to create an atomic bomb meant that it was of the utmost importance and urgency that the Allies got there first. Enormous amounts of money were ploughed into the project - $2 billion in total, or the equivalent of $24 billion today.

Headquartered in Manhattan (hence the name), the project was spread across three sites - Oppenheimer’s Los Alamos laboratory, which focused on bomb design, construction and testing, Hanford in Washington, which was responsible for plutonium production, and Oak Ridge in Tennessee, which focused on uranium enrichment.

The scientists working at Los Alamos successfully created two types of bomb - ‘Little Boy’, which used uranium-235, and ‘Fat Man’, which used plutonium-239. The testing of the second type of these weapons was codenamed ‘Trinity’. As the time ticked down to the detonation of the bomb, the Italian-American physicist Enrico Fermi jokingly took bets that the explosion would set fire to the Earth’s atmosphere and destroy all life. How he planned to collect on this bet has, sadly, been lost to history.

‘I am become Death, the destroyer of worlds.’

Trinity successfully detonated at 5:29am on 16th July 1945. Upon witnessing the largest man-made explosion the world had ever seen, a passage from the Hindu Bhagavad Gita sprung to Oppenheimer’s mind:

‘If the radiance of a thousand suns were to burst at once into the sky, that would be like the splendour of the mighty one.’

After the test, Oppenheimer was exuberant, even expressing the view that it was a shame that the bomb had not been delivered in time to be used on Nazi Germany. However, after the bomb was used first on the city of Hiroshima on 6th August and then on Nagasaki three days later, Oppenheimer had a very swift change of heart.

He and his colleagues could not see why the bombing of Nagaski had been necessary and he travelled to Washington to deliver a letter to the US Secretary of War. In his letter, Oppenheimer expressed his horror at the use of the bomb on Nagasaki and said that he wished to see all nuclear weapons banned.

Granted an audience with President Harry Truman in October 1945, Oppenheimer went further. He told the president that he felt he had ‘blood on his hands’. This infuriated Truman, who told his Under Secretary of State that he never wanted ‘to see that son-of-a-bitch in this office ever again’. Oppenheimer’s war was over. The genie he unleashed was well and truly out of its bottle.

After the bomb

Japan surrendered on 11th August 1945, bringing an end to the most destructive conflict in human history. A top-secret project right up until the moment the first atomic bomb exploded over Hiroshima, Oppenheimer quickly became a national hero, gracing the covers of Time and Life magazines.

After the war, Oppenheimer became a critic of nuclear proliferation and a very vocal opponent of the hydrogen bomb, even being questioned by J. Edgar Hoover’s notorious House Un-American Activities Committee in 1949 over his prewar communist leanings. This eventually led to Oppenheimer being stripped of his security clearance in 1954, bringing an end to his career as a government scientist. His warnings about developing the hugely more destructive hydrogen bomb went unheeded. On 1st November 1951, the United States successfully tested the world’s first thermonuclear device. The British followed suit in 1952 and the Soviets in 1955. A nuclear arms race followed, and the world would never be the same again.

Oppenheimer lived out the rest of his life lecturing throughout Europe and Japan. In 1957, he was awarded France’s highest honour, the Legion of Honour, and he was elected a member of the prestigious Royal Society of Great Britain in 1962. Rehabilitation in his homeland came in 1963, when President Kennedy awarded him the Enrico Fermi Award for international achievement in science. The award, alongside a $50,000 tax-free stipend, was presented to him by President Lyndon Johnson following Kennedy’s assassination in 1963.

A lifelong chain smoker, Oppenheimer was diagnosed with throat cancer in 1965. He died on 15th February 1967 at the age of 62.