How and why did America involve itself in the Korean conflict of the 1950s?

America became involved in the Korean conflict of the 1950s primarily to contain the spread of communism in Asia, following the Cold War policy of containment. After North Korea, backed by the Soviet Union and China, invaded South Korea in June 1950, the U.S. intervened under the auspices of the United Nations to support South Korea. The U.S. feared that the fall of South Korea to communism could trigger a domino effect in the region, leading to further communist expansion. This military involvement marked a significant escalation in Cold War tensions and set a precedent for U.S. engagement in conflicts worldwide.