Final answer:
NATO was created on April 4, 1949, to provide a system of collective defense for its members against potential Soviet aggression, marking a pivotal moment in Cold War history.
Step-by-step explanation:
The goal of the North Atlantic Treaty Organization (NATO) on April 4, 1949, was to establish a system of collective defense whereby its member states agreed that an attack against one would be considered an attack against them all. The organization was formed in response to increasing tensions in post-war Europe and the threat of Soviet aggression. The founding members included the United States, Canada, and ten Western European nations, such as Britain and France, with the principle of mutual military assistance at its core. NATO's establishment prompted the Soviet Union to form their own alliance, the Warsaw Pact. The creation of NATO was a significant event in the history of international relations and played a central role in the Cold War era.