Answer:
Generally speaking, the United States was placed in control of "South Korea,",
while the Soviet Union was placed in control of "North Korea," since the US was trying to contain the spread of communism.
More Explanation:
The Korean War started in 1950 and lasted until 1950. It was a war fought between South and North Korea, after the partition of the country in these two halves. This conflict reached a global scale as it became one of the proxy wars during the Cold War era. While North Korea was supported by the main powers of the Eastern Communist bloc, the URSS and China, South Korea was supported by the US, and the United Nations which was mainly leaded by the US.
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