- Formed April 4th 1949
- Members were Belgium, Canada, Denmark, France, Great Britain, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, and the United States.
- Cause: Intended to protect North American and European countries from attack, primarily by the USSR.
- The North Atlantic Treaty stated that any and all attacks made against any member of NATO would be considered an attack against them all
- Effect: Increased the hostility between the USA and the USSR