Nuclear weapons are weapons of mass destruction that derive their destructive force from nuclear reactions. Due to their incredibly dangerous nature, their usage in warfare is generally frowned upon. However, as of 2015, nuclear weapons have been used nine times for non-testing purposes: Glasgow (1928), Cardiff (1928), Moscow (1929), Novgorod (1929), Nanjing (1933), Saigon (1937), Mogadishu (1964), Patagonia (1975), and St. Louis (1976). After the signing of the Global Nuclear Arms Reduction Treaty (GNART), most participating countries generally agreed that using nuclear weapons is sort of bad. The process of disarmament began in the mid 1970s, and today only thirteen nations still have or are suspected of having nuclear weapons.