Why, and With what Success, Did the UN intervene in Korean War?

In the beginning, the United Nations Temporary Commission on Korea was established in 1945 as a general world peacekeeping organization. This was set up to organize elections and built a democratic government. However, North Korea and the USSR refused to cooperate with the commission. On 25 June 1950 military forces from North Soviet Korea attacked the American South Korea. It seemed as a proxy war between the USSR and US, but in fact this attack was mainly decided by Kim Il Song, leader of North Korea, alone. With in a month, North Korean army controlled the whole peninsula apart from Pusan.
The Western Countries and US saw it as an invasion and expansion of Communism in Asia.…