回复：时空与地缘政治使中国比然倒像苏俄。如果倒像美国，苏俄必有反应，苏强我弱，北方边境漫长，大兵随时可

Also, let's see what the situation was before China intervened. 7th Fleet was already deployed to the Taiwan Strait so the liberation of Taiwan was militarily impossible. The US forces have completely overrun North Korea up to the Yalu River. Even assuming (a big assumption) that US had no intention of invading China. If you were Mao, how would you feel if there were hostile forces at Northeast and in the East. Despite the losses, the war was fought in a foreign soil and not in China. Those days were gone. Remember the battleground of Japanese Russian was in China.
The came the Vietnam war, do you think the ground war would stop at the 17th line if it weren't because of the Korean War.