Race for the Nuclear Bomb

History of nuclear weapons chronicles the development of nuclear weapons. Nuclear weapons are devices that possess enormous destructive potential that uses energy derived from nuclear fission or nuclear fusion reactions. Starting with the scientific breakthroughs of the 1930s which made their development possible, continuing through the nuclear arms race and nuclear testing of the Cold War, and finally with the questions of proliferation and possible use for terrorism in the early 21st century.

The first fission weapons, also known as "atomic bombs," were developed in, and partially by, the United States during World War II in what was called the Manhattan Project. In August 1945 two were dropped on Japan. An international team was dispatched to help work on the project.

The Soviet Union started development shortly thereafter with their own atomic bomb project, and not long after that both countries developed even more powerful fusion weapons also called "hydrogen bombs." During the Cold War, these two countries each acquired nuclear weapons arsenals numbering in the thousands, placing many of them onto rockets which could hit targets anywhere in the world. Currently there are at least nine countries with functional nuclear weapons. A considerable amount of international negotiating has focused on the threat of nuclear warfare and the proliferation of nuclear weapons to new nations or groups.

There have been (at least) four major false alarms, the most recent in 1995, that almost resulted in the US or Russia launching its weapons in retaliation for a supposed attack.

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Nuclear armed countries produce it in US - Russia - UK - France - China - Israel - India - Pakistan and the latest is North Korean

1 - United States United States: Warheads active - 2,700 (total: 9,400 / first test: 1945 "Trinity")
2 - Russia (former Soviet Union): Warheads active - 4,840 (total: 13,000 / first test: 1949 ("RDS-1"))
3 - United Kingdom: Warheads active - 160 (Total: 185 / first test: 1952 "Hurricane")
4 - France: Warheads active - 300 (Total: 300 / first test: 1960 "Gerboise Bleue")
5 - China: Warheads active - 180 (total: 240) / first test: 1964 "596")

Non-NPT nuclear powers

6 - India: Warheads active - ? / (Total: 60 / first test: 1974 "Smiling Buddha")
7 - Pakistan: Warheads active - ? / (Total: 60 / first test: 1998 "Chagai-I")

States accused of having nuclear weapons

8 - Israel: Warheads active - ? / (Total: 80 / unknown or 1979, see Vela Incident)
9 - North Korea: Warheads active - ? / (Total: <10 2006="2006" br="br" first="first" test="test">
The nuclear powers have conducted at least 2,000 nuclear test explosions which most are far stronger then the atom bomb which distroy Hiroshima (numbers are approximated, as some test results have been disputed):

1- United States: 1,054 tests by official count (involving at least 1,151 devices, 331 atmospheric tests), most at Nevada Test Site and the Pacific Proving Grounds in the Marshall Islands, with ten other tests taking place at various locations in the United States, including Amchitka Alaska, Colorado, Mississippi, and New Mexico.
2- Union Soviet Union: 715 tests (involving 969 devices) by official count, most at Semipalatinsk Test Site and Novaya Zemlya, and a few more at various sites in Russia, Kazakhstan, Turkmenistan, and Ukraine.
3- France: 210 tests by official count (50 atmospheric, 160 underground), 4 atomic atmospheric tests at C.E.S.M. near Reggane, 13 atomic underground tests at C.E.M.O. near In Ekker in the then-French Algerian Sahara, and nuclear atmospheric tests at Fangataufa and nuclear undersea tests Moruroa in French Polynesia. Additional atomic and chemical warfare tests took place in the secret base B2-Namous, near Ben Wenif, other tests involving rockets and missiles at C.I.E.E.S, near Hammaguir, both in the Sahara.
4- United Kingdom: 45 tests (21 in Australian territory, including 9 in mainland South Australia at Maralinga and Emu Field, some at Christmas Island in the Pacific Ocean, plus many others in the U.S. as part of joint test series)
5- China: 45 tests (23 atmospheric and 22 underground, at Lop Nur Nuclear Weapons Test Base, in Malan, Xinjiang)
6- India: 6 underground tests (including the first one in 1974), at Pokhran.
7- Pakistan: 6 underground tests, at Ras Koh Hills, Chagai District and Kharan Desert, Kharan District in Balochistan Province.
8- North Korea: 2 tests at Hwadae-ri 2006 and on 2009.

Additionally, there may have been at least three alleged but unacknowledged nuclear explosions. Of these, the only one taken seriously as a possible nuclear test is the Vela Incident, a possible detection of a nuclear explosion in the Indian Ocean in 1979, hypothesized to have been a joint Israeli/South African test.