Truman signs North Atlantic Treaty, founding NATO with 11 European allies and committing U.S. forces to European defense

President Harry Truman signs the North Atlantic Treaty on April 4, 1949, creating the NATO military alliance with Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, and the United Kingdom. Article 5 commits each member to treat an armed attack on one as an attack on all. The treaty formalizes the U.S. military commitment to European security and the permanent basing of American troops in West Germany — an arrangement that continues for 77 years.