The US policy expressed in military manner with the involvement in the Korean War is the policy of containment, in which the US believed that they have to stop the spread of Communism by supplying and backing up forces and governments of anti-communists. In the case of the Korean War, the US supported the R.O.K, and was able to successfully contain the spread of Communism in that particular war.
i wish i knew the answer to this. the world is unperfect as well as the people in it. you cant change anyone, but always be the change that you want to se in the world. always treat others the way you want to be treated