Nuclear weapons are weapons that get power from nuclear reactions and have tremendous destructive power - a nuclear bomb capable of destroying a city. Nuclear weapons were used only twice in combat - during World War II by the United States against the cities of Japan, Hiroshima and Nagasaki. At that time the explosive power of the nuclear bomb dropped on Hiroshim and Nagasaki was 20 kilos (thousands) tons of TNT. While the current nuclear bomb is capable of exploding more than 70 mega (millions) tons of TNT
The confirmed nuclear weapons countries are the United States, Russia, the United Kingdom (Britain), France, the People's Republic of China, India, North Korea and Pakistan. In addition, the state of Israel is believed to have nuclear weapons, although not tested and Israel is reluctant to confirm whether it has nuclear weapons or not. See a list of countries with further nuclear weapons.
Plans to make uranium bombs by Allied countries began in 1939 when Albert Einstein wrote a letter to US President Franklin D. Roosevelt and theorized that uncontrolled nuclear chain reactions had great potential for weapons of mass murder. In 1940, the US government approved a fund of 6,000 dollars to finance the manufacture of the atomic bomb. The project, called the Manhattan project, finally achieved results five years later with funds swelling to two million dollars. The next question is to whom will the bomb be dropped? Target is Germany. However, because Germany had surrendered in World War II, in August 1945 Japan became a victim of the first generation atomic bomb attack.
