USA HISTORY

Detailed explanation-1: -Even so, the North Korean invasion came as an alarming surprise to American officials. As far as they were concerned, this was not simply a border dispute between two unstable dictatorships on the other side of the globe. Instead, many feared it was the first step in a communist campaign to take over the world.

Detailed explanation-2: -This had not gone unnoticed by the Chinese and Mao Zedong was especially fearful of the presence of U.S troops along his border. At the invitation of the North Koreans, a massive volunteer army of Chinese troops invaded Korea and pushed the UN forces all the way back down the Korean Peninsula.

Detailed explanation-3: -UN forces invaded North Korea in October 1950 and moved rapidly towards the Yalu River-the border with China-but on 19 October 1950, Chinese forces of the People’s Volunteer Army (PVA) crossed the Yalu and entered the war.