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The United States

Introduction: The United States was the first state to acquire nuclear weapons. The US nuclear program started during WWII, and the first nuclear weapon test was conducted on July 16, 1945. In August 1945, the United States dropped nuclear bombs on Japanese cities Hiroshima and Nagasaki. On November 1, 1952, the United States conducted its first hydrogen bomb (fusion) test. The United States acceded to the nuclear Non-Proliferation Treaty (NPT) as a nuclear-weapon state (NWS) in 1968.


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Early on in the development of its nuclear weapons, the United States relied on information-sharing with both the United Kingdom and Canada. US President Dwight D. Eisenhower initiated the Atoms for Peace program in 1953 to encourage peaceful use of nuclear technology and prevent the spread of nuclear weapons. However, the program allowed a number of states (India, Pakistan, South Africa, Israel) to profit from dual-use technology and develop their own nuclear arsenals.

It is estimated that the United States possesses 5,200 nuclear warheads, consisting of approximately 2,700 operational warheads ((2,200 strategic and 500 nonstrategic), and of about 2,500 additional warheads in reserve. An additional 4,200 warheads await dismantlement.

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