NATO Headquarters, Brussels, Belgium
April 4, 1949, 75 years ago: NATO, the North Atlantic Treaty Organization, is founded in Washington, D.C. President Harry S Truman and Secretary of State George C. Marshall set it up as a military alliance of Western Europe, where "An attack on one of us is an attack on all of us."
The founding members of NATO were America, Canada, Britain, France, Italy, Belgium, the Netherlands, Luxembourg, Norway, Denmark, Iceland and Portugal. On February 18, 1952, with the Truman Doctrine having proven successful, and with both nations having participated in the United Nations' effort to protect South Korea during the Korean War, Greece and Turkey were admitted to NATO. On May 6, 1955, 10 years to the week after V-E Day, West Germany was admitted.
It would be a long time before new additions were made. Spain, neutral in both World Wars, were admitted in 1982. With the collapse of the Soviet-influenced counterpart, the Warsaw Pact, NATO waited 10 years before inviting any new members. The Czech Republic, Hungary and Poland were admitted in 1999. Bulgaria, Romania, Slovakia, the former Yugoslav nation of Slovenia, and the "Baltic States" of Lithuania, Latvia and Estonia were admitted in 2004.
Albania and the former Yugoslav nation of Croatia were admitted in 2009. The former Yugoslav nation of Montenegro was admitted in 2017. The former Yugoslav nation of North Macedonia was added in 2020.
UPDATE: Finland, long neutral, was admitted in 2023. Sweden, also neutral through both World Wars and the Cold War, has also expressed interest in joining.
And Ukraine wants to join as well, but that's not possible as long as Russia is attacking them: It would mean that every NATO nation, including America, would have to go to war with Russia, and that would mean World War III.
Donald Trump ran for President in 2024, saying that if NATO members did not pay their dues, "I would encourage Russia to do whatever the hell they want." Including attack a NATO member.
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