Nuclear weapons came about as a result of the United States’ famous Manhattan Project during World War II. The first atomic test, called Trinity , took place in New Mexico on July 16, 1945 with an explosive yield of 19 to 21 kilotons. In the course of the next seventy years, the Bomb appeared in the arsenals of many nations on virtually every continent: Russia (USSR), France, China, India, Pakistan, North Korea and Israel.
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