The NATO Agreement is Signed in Washington DC
The Treaty of Brussels, signed on 17 March 1948 by Belgium, the Netherlands, Luxembourg, France and the United Kingdom is considered the precursor to the NATO agreement.
The treaty and the Soviet Berlin Blockade led to the creation of the Western European Union's Defense Organization in September 1948. However, participation of the United States was thought necessary in order to counter the military power of the USSR, and therefore talks for a new military alliance began almost immediately.
These talks resulted in the North Atlantic Treaty, which was signed in Washington, D.C. on 4 April 1949. It included the five Treaty of Brussels states, as well as the United States, Canada, Portugal, Italy, Norway, Denmark and Iceland. Popular support for the Treaty was not unanimous; some Icelanders commenced a pro-neutrality, anti-membership riot in March 1949.
The Parties of NATO agreed that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all. Consequently they agree that, if such an armed attack occurs, each of them, in exercise of the right of individual or collective self-defense will assist the Party or Parties being attacked, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area.”— From the NATO Agreement
The Cold War was in full swing, as the Soviet Union was rising to power, capturing satellite countries. Using their strong dynamic forces, the Soviet Union captured surrounding countries first to help protect them from any invasion. This tactic was used to imprison civilians and force them to join the Soviet military. As their armed forces greatly increased in numbers, other countries and nations feared that the Soviet Union would expand their control and take over other countries.