Why did Truman believe it was important to protect south Korea?

President Harry S. Truman believed it was important to protect South Korea to contain the spread of communism in Asia, particularly in the context of the Cold War. The invasion of South Korea by North Korea in 1950 was seen as a direct challenge to the U.S. policy of containment, which aimed to prevent the expansion of communist influence. By defending South Korea, Truman sought to uphold U.S. commitments to allies and demonstrate American resolve against communist aggression, thereby maintaining stability in the region.