North Atlantic Treaty Organization, NATO

The North Atlantic Treaty Organization (NATO) is an international military bloc established by the United States and its Western European allies to strengthen their collective defence against the military and ideological expansion of the Soviet Union. Founded in 1949 and headquartered in Brussels, Belgium, it currently has 19 member States and 23 Partnership for Peace countries. Its purpose is that the States parties should join together in the exercise of collective defense, and that in the event of war between any of the States parties and another State, the other States parties should provide assistance, including force support.