Weapon with the capacity to inflict death and destruction indiscriminately and on a massive scale. The term has been in currency since at least 1937, when it was used to describe massed formations of bomber aircraft. Today WMDs are nuclear, biological, or chemical weapons—frequently referred to collectively as NBC weapons. Efforts to control the spread of WMDs are enshrined in international agreements such as the Nuclear Non-proliferation Treaty of 1968, the Biological Weapons Convention of 1972, and the Chemical Weapons Convention of 1993. See nuclear weapon; chemical warfare; biological warfare.
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