Answer:
North Korea invaded South Korea in June of 1950. A UN army of almost a dozen countries came to South Korea's aid.
Step-by-step explanation:
Five years after the country's division, North Korean dictator Kim Il Sung decided to try to reunify it. Kim invaded South Korea on June 25, 1950.
President Harry Truman and his advisers believed the Soviet Union had backed the invasion and refused to allow communism to expand anyplace in the world. Two days after the invasion, the US gathered the UN Security Council to help South Korea. A US-led UN coalition invaded South Korea.
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