NATO (North Atlantic Treaty Organization) was formed on April 4, 1949. It was established as a military alliance of capitalist countries primarily from the Northern hemisphere, created to provide collective security—meaning an armed attack against one member would be considered an attack against all, requiring mutual defense assistance. The original 12 founding members were the United States, Canada, the United Kingdom, France, Belgium, the Netherlands, Luxembourg, Norway, Iceland, Denmark, Italy, and Portugal. NATO was formed mainly as a deterrent against Soviet expansion in Europe after World War II and to foster political integration among its members.
