Why did the united states get in the war in korea

In 1950 the Korea Peninsula was divided between a Soviet-backed government in the north and an American-backed government in the south. The division of Korea into two halves had come at the end of World War II. In August of 1945 the Soviet Union invaded Korea, which had been under Japan's control since 1910

Explanation:

answer; it divides government into (3) three branches of government have unlimited

the anwser is missions