April 4 in American History

April 4, 1949 — NATO is founded

The United States and eleven allies signed the North Atlantic Treaty, creating a mutual-defense alliance to deter Soviet aggression: an attack on one would be treated as an attack on all. It anchored American leadership of the free world for the Cold War and beyond — one of the most consequential alliances in history.

Common Questions About April 4

What happened on April 4 in American history?

In 1949: NATO is founded. The United States and eleven allies signed the North Atlantic Treaty, creating a mutual-defense alliance to deter Soviet aggression: an attack on one would be treated as an attack on all.

Why is April 4 significant?

The United States and eleven allies signed the North Atlantic Treaty, creating a mutual-defense alliance to deter Soviet aggression: an attack on one would be treated as an attack on all. It anchored American leadership of the free world for the Cold War and beyond — one of the most consequential alliances in history.

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