The first time nuclear weapons were used was in 1945.  First was the Trinity Test, south of Socorro New Mexico, USA on 16 July 1945. On 6 August, 1945, the United States dropped a nuclear weapon on the city of Hiroshima, Japan and three days later on 9 August, the US dropped another nuclear bomb over the city of Nagasaki.

History of nuclear weapons

The Trinity Test

The Trinity Test at Alamogordo was the first nuclear weapon explosion. It was a plutonium bomb, developed by Robert Oppenheimer and his team. Like those that followed, it caused irreversible damage to the environment and surrounding communities. The harm wrought by nuclear weapons on people and environments began with the Trinity test at 5:29 am on 16 July. The people living downwind were given no advance warning of the explosion and were the first to experience the devastating humanitarian impacts of nuclear weapons.

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Bombing Hiroshima

On 6 August, 1945, the United States became the first - and to date only - country to use nuclear weapons in war by dropping a uranium bomb over the city of Hiroshima. The bomb killed more than 140,000 over the course of the next few months, and devastated the city beyond recognition. Many more died in the years following. Those who survived the bombing are called "hibakusha".

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Bombing Nagasaki

Three days later, the US dropped a plutonium bomb over the port city of Nagasaki, killing an estimated 74,000 by the end of 1945. This was the last time nuclear weapons have been used in war, but nuclear weapons continued to be exploded for decades in nuclear testing programmes across the globe. To date more than 2000 nuclear weapons have been detonated around the world.

The Hibakusha (survivors of the bombings of Hiroshima and Nagasaki) are integral to the history of the atomic bombings of these cities - not only because they are among the few true nuclear weapons experts given they have experienced the actual impact of these weapons - but also because of the tireless efforts of many Hibakusha to eliminate nuclear weapons.

To learn more, you can find a vast number of Hibakusha testimonies online, but good starting places are Hibakusha Stories and the 1945 project, as well as these resources by the Hiroshima Peace Memorial Museum and the Nagasaki Atomic Bomb Museum.

Nuclear weapons are man made and we can choose to eliminate and dismantle them

While more than 30 countries considered building nuclear weapons, the majority chose against investing resources in these weapons of mass destruction. Several countries were moving close to a nuclear programme, but chose to change their plans. One country that did develop nuclear weapons, South Africa, chose to get rid of them. Keeping nuclear weapons is a choice, and there is always an opportunity to choose to dismantle and eliminate them instead.