North American Treaty was signed in 1949. Twelve nations formed the original North American Treaty Organization: Belgium, Canada, Denmark, France, Great Britain, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, and the United States. Greece and Turkey became members in 1951, and West Germany joined in 1954. Spain became the last member in 1982. The main purpose of NATO is protection; an attack against one member is an attack against all members. Idea: Children could locate these countries on a world map and decide whether all countries benefit equally from this treaty. Children can learn ore at: NATO.