On June 27, 1950, the UN Security Council passed Resolution 83, calling on member nations to help South Korea repel the North Korean invasion that had begun on June 25. The United States, acting under this mandate, committed air and naval forces the same day, transforming a border conflict into an international war that would last three years and cost millions of lives.
When North Korean tanks rolled south on June 25, 1950, the Truman administration moved with unusual speed. The Soviet Union, boycotting the Security Council over the exclusion of Communist China, was absent to cast a veto, leaving the path clear for the UN to act. Resolution 83 passed with only Yugoslavia abstaining, and President Truman ordered US air and naval forces into action within hours of its passage.
The absence of a Soviet veto that day would become one of the great ironies of Cold War diplomacy — a boycott meant to punish the UN instead allowed it to authorize the first major military action under the UN flag. Sixteen nations would eventually send combat troops.
The war that followed devastated the Korean peninsula, killed an estimated 3 million people, and ended in 1953 not with a treaty but an armistice — leaving Korea divided along almost the same line to this day.
Key people: Harry S. Truman, Kim Il-sung, Syngman Rhee