The National Atlantic Treaty Organization was formed in:

🧠 Explanation:

It was established through the signing of the North Atlantic Treaty in Washington, D.C., by 12 founding countries, including the United States, Canada, the United Kingdom, and several Western European nations. The main purpose of NATO was to create a collective defense alliance against potential aggression during the early Cold War, particularly in response to the growing influence of the Soviet Union. The treaty’s core principle, outlined in Article 5, states that an armed attack against one member is considered an attack against all, ensuring mutual protection and cooperation among member states.