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Key Issues Nuclear Weapons History Presidential Policies Truman Nuclear Events

President Harry S. Truman - Nuclear Events


Secretary of War Stimson and General Groves brief President Truman on the bomb.

Leo Szilard visits White House with letter of introduction from Albert Einstein to warn President Truman of the dangers that atomic weapons pose for the post-War world and to urge him not to authorize use of atomic weapons against Japan.

US scientists perform first successful A-Bomb test at Alamogordo, New Mexico.

Truman meets Stalin and Churchill at Potsdam and tells Stalin about the A-bomb.Truman approves General Grovesí recommendation to use the A-bomb on Japan.

US drops “Little Boy” nuclear bomb on Hiroshima, immediately killing 140,000 citizens. Use of the A-Bomb in WWII - Statement by the President Announcing the Use of the A-Bomb at Hiroshima.

Little Boy

US drops “Fat Man” nuclear bomb on Nagasaki, immediately killing 70,000 citizens.

Fat Man

Fat Man Mushroom Cloud

Hiroshima and Nagasaki, PBS video

Truman adopts the Truman-Attlee-King declaration (New Quebec agreement). The President's News Conference following the signing of a Joint Declaration on Atomic Energy.

Soviets notify the US that they are developing the A-bomb.

Truman declares that all US land with fissionable material is subject to government use and ownership. (These rights are later given to the AEC in December.) Executive Order 9701

US performs A-bomb test at Bikini Atoll. Statement by the President Concerning Preparations for Nuclear Tests in the Pacific.

Truman signs Atomic Energy Act (Public Law 79-585/McMahon Act), creating an Atomic Energy Commission (AEC) to replace the Manhattan Engineering Distict (MED). Earlier Letter to Senator McMahon  regarding energy bill. Trumanís Reflection on Atomic Energy bill two years later.

December 1946
Truman gives Atomic Energy Commission (AEC) jurisdiction over US fissile materials and sites. Executive Order 9816

Truman plans for new A-bombs. Trumanís Diary Entry.

US performs A-bomb tests at Eniwetok. Trumanís letter to Secretary Forrestal on the Atomic Weapons Tests at Eniwetok.

The Soviets perform their first successful A-bomb test, referring to it as ďFirst LighteningĒ while the US called it Joe 1 after Stalin. Trumanís Statement to the American public.

Truman announces US plans to develop the H-bomb. Audio, Representative Henry Jackson on the H-Bomb Decision.

USSR explodes another A-bomb. Statement Directed by Truman Addressing Recent USSR A-Bomb Explosion.

Truman establishes airspace reservation over the Las Vegas Project in Las Vegas, Nevada. This site would eventually witness around 1000 nuclear tests. (Natural Resources Defense Council, Nuclear Weapons Databook Project). Executive Order 10218

Truman establishes airspace reservation over the Savannah River Plant of the US AEC.