History

At the initiative of the physicist Leo Szilar, Albert Einstein and Szilar wrote a letter to US President Franklin D Roosevelt in the fall of 1939, warning that Germany might use the newly discovered knowledge of nuclear fission to develop atomic weapons. After Japan’s attack on Pearl Harbor in December 1941, the United States was drawn into World War II. This created the military and economic conditions for a major investment in the development of nuclear weapons.

In 1942, the United States launched the Manhattan Project with the aim of developing an atomic bomb. The plan was to beat Germany, which was also said to be working on developing an atomic bomb. The Manhattan Project was very extensive and, according to one source, at one point over 600,000 people were working on the project. In 1943, Canada and the United Kingdom also joined the project.

General Leslie Groves was responsible for the military aspects of the project, and the scientific work was led by Robert Oppenheimer, a professor of physics. The research took place at several different locations, including Oak Ridge in Tennessee, Hanford in Washington State, and Los Alamos in New Mexico.

The starting point for what has come to be known as the ‘atomic age’ was a plutonium bomb called Trinity. At 05:29:45 on the morning of 16 July 1945, the bomb detonated at the Alamogordo test site in New Mexico, USA. The bomb had an explosive power equivalent to approximately 20 kilotons of TNT.

Physicist Robert Oppenheimer, one of the key figures in the Manhattan Project, has become known as the ‘father of the atomic bomb’ for his work on the first atomic bomb.

When Trinity detonated at the test site, Oppenheimer is said to have quoted a passage from the Hindu scripture Bhagavadgita: ‘If a thousand suns were to burst into the sky, it would be like the glory of the mighty. Now I am become Death, the destroyer of worlds.’

Some say that US President Truman wanted to force the Japanese army to surrender in order to quickly end the raging Second World War. That is why he gave the order to bomb Japan with an atomic bomb. At the same time, Truman wanted to show Soviet leader Stalin what the US had in its arsenal, even though the Soviet Union was currently an ally.

On 6 August 1945, a bomber was loaded to drop the atomic bomb, called Little Boy, on the Japanese port city of Hiroshima. The attack with this weapon, which had essentially never been tested before, was as much a test as anything else. The idea was also to see what effects the atomic bomb would have on built-up areas, as it had not been tested before.

Two-thirds of Hiroshima was destroyed, and by the end of the war in 1945, over 140,000 people had died from the immediate and long-term effects of the bomb.

Three days later, on 9 August 1945, the United States dropped another atomic bomb. It was named Fat Man and was dropped on the Japanese city of Nagasaki. Approximately 74,000 people died in Nagasaki as a result of the atomic bomb.

The bombings of Hiroshima and Nagasaki prompted the leaders of the Soviet Union to immediately launch a comprehensive project to catch up with the United States. They received significant help from spies who believed that the United States should not have a monopoly on nuclear weapons. The first Soviet nuclear weapon was test detonated in 1949. This marked the start of the nuclear arms race.

The development of larger nuclear weapons and hydrogen bombs then continued very rapidly in both the United States and the Soviet Union. In 1951 and 1953, respectively, the United States and the Soviet Union detonated their first hydrogen bombs.

On 3 October 1952, the United Kingdom conducted its first nuclear test, called Operation Hurricane, on the Montebello Islands in Western Australia.

Max Kimber, a soldier who participated in the British nuclear tests, described the effect on wildlife: “There were hundreds of thousands of dead turtles on the beach. They had come up on the beach and been killed by the radiation. It was full of turtles from one end of the place to the other.”

In 1957, the United Kingdom detonated its first hydrogen bomb. In 1958, the country began cooperating with the United States, and British tests were subsequently conducted in the Nevada Desert in the United States.

In 1958, the United States and the Soviet Union decided to temporarily suspend nuclear testing. At the time, it was believed that there was an opportunity to negotiate an agreement on nuclear testing. However, political and military events meant that the suspension was short-lived.

In 1961, the Soviet Union broke the ceasefire and quickly detonated 30 bombs, including the world’s largest hydrogen bomb to date, the Tsar Bomb, with a yield of 57 megatons. By comparison, the bomb dropped on Hiroshima had a yield of 20 kilotons. Following the Soviet Union’s test explosions, the United States resumed its test explosions in the Pacific Ocean.

On 13 February 1960, France declared itself the fourth nuclear-weapon state by testing a nuclear weapon in the Algerian desert.

During the Cold War, there was an intense arms race between the United States and the Soviet Union. The states spied on each other’s nuclear arsenals, and every time one of them was suspected of increasing its arsenal or acquiring a new type of nuclear weapon, the other followed suit, happy to be able to surpass the enemy by a few steps.

Nothing could stop the arms race, as there was a risk that the enemy would acquire increasingly powerful nuclear weapons. Both states had nuclear weapons aimed at each other, ready to be launched within minutes. Both states also had advanced warning systems to identify a hostile nuclear attack and respond to the attack with a counterattack – before their own territory had been hit.

In October 1962, the world was on the brink of nuclear war during the Cuban Missile Crisis, when the Soviet Union planned to place nuclear missiles in Cuba, something the United States opposed. For two weeks, the rest of the world held its breath, and at the end of October, the crisis was resolved.

The arms race reached its absolute peak in 1986, when the two superpowers together had 70,500 nuclear weapons.

China began its nuclear weapons programme in the mid-1950s, after the Korean War. Initially, they received help from Soviet advisers and equipment. However, increasingly frosty relations between the two countries led to the Soviet Union withdrawing all support. In 1964, China detonated its first atomic bomb in Lop Nur in the Gobi Desert, and in 1967, the country tested its first hydrogen bomb.

In 1968, a Treaty on Nuclear Disarmament and Non-Proliferation was negotiated, and in 1970, the Non-Proliferation Treaty, NPT, entered into force. The agreement consists of three pillars: non-proliferation, disarmament and the peaceful use of nuclear energy. The agreement defined the then five nuclear-weapon states as nuclear-weapon states in exchange for their dismantling their nuclear arsenals: the United States, the Soviet Union, the United Kingdom, France and China.

Four nuclear-weapon states have not signed the treaty and are not recognised by it: India, Pakistan, and Israel. North Korea is the only country that left the treaty and then developed nuclear weapons.

The nuclear-weapon states have not yet fulfilled their commitment in Article 6 of the treaty to disarm, and even today, the nuclear-weapon states are modernising their nuclear arsenals and developing new nuclear weapons.

Israel’s nuclear weapons programme and nuclear weapons stockpile were revealed in 1986 by Israeli nuclear physicist Mordechai Vanunu in the British media. Mordechai Vanunu was kidnapped and imprisoned by Israel and spent 18 years in prison, 11 of which were spent in solitary confinement.

Since the Partial Test Ban Treaty (PTBT) did not ban underground nuclear tests, nuclear weapon states continued to conduct underground tests. Under strong international pressure, negotiations continued on a treaty banning all nuclear tests. This led to the Comprehensive Test Ban Treaty (CTBT), which was negotiated in 1996, but the treaty has still not entered into force.

The agreement has not yet entered into force because certain states must accede to the agreement but have not yet done so. These are China, Egypt, India, Israel, North Korea, Pakistan, Russia and the United States. However, all of these states have refrained from conducting tests since 1998, including underground tests, with the exception of North Korea.

India conducted what it called a ‘peaceful’ test explosion in 1974, named ‘Smiling Buddha’, and declared itself a nuclear power in 1998 after conducting a series of nuclear tests at the Pokhran facility in Rajasthan.

Following India’s test explosion in 1974, Pakistan began developing its nuclear weapons programme and tested its first nuclear weapon in 1998. This marked the beginning of an arms race between the two countries, which has been strongly condemned by the UN Security Council.

In 2003, North Korea withdrew from the Non-Proliferation Treaty, and in 2006, the country conducted its first test explosion. The yield was low, and the test explosion was probably a partial failure. The test was strongly condemned by the UN Security Council, which described the test explosion as a ‘clear threat to international peace and security’.

North Korea has conducted a total of six nuclear tests. The latest explosion is believed to have been a hydrogen bomb with an explosive yield of between 70 and 280 kilotons.

In 2017, the UN Treaty on the Prohibition of Nuclear Weapons (TPNW) was negotiated at the UN headquarters in New York. The TPNW is the first of its kind to consistently prohibit the use, threat of use, testing, development and production of nuclear weapons. The treaty came into force in January 2021.

Einstein-Szilard letter, Atomic Herritage Foundation
The Nuclear Security Blog, “How many people worked on the Manhattan Project?”, Alex Wellerstein
Atomic bombings of Hiroshima and Nagasaki, Britannica
Hydrogen Bomb – 1950, Atomic Heritage Foundation
The Soviet Response, Atomicarchive.com
U.S. and UK Nuclear Cooperation After 50 Years, Center for Strategic and International Studies
The Power of Women Strike for Peace, Kathy Crandall Robinson, Arms Control Association
Nuclear Close Calls: The Cuban Missile Crisis, Atomic Heritage Foundation
Treaty on the Non-Proliferation of Nuclear Weapons, United Nations Office for Disarmament Affairs
The Spread of Nuclear Weapons: China, Britannica
Mordechai Vanunu, Right Livelihood
The Treaty, International Campaign to Abolish Nuclear Weapons, ICAN