i like this idea maybe the soviets get involved, they disliked that chinese even more than the americans at this point, kruschev and eisenhower were pretty chummy...
The Sino-Soviet Split wasn't until the 1960s. At this point, the Chinese are still very much dependent on the USSR and very close ideologically. Have you forgotten the Soviet pilots over Korea? Also, Stalin was in power at this time, not Khrushchev. He didn't take full power until 1956, IIRC.
If the US starts to launch a full-scale attack on China, it's unlikely that the USSR will get directly involved, though you can expect a hell of a lot of weapons supplies for the Chinese. The US attack will likely get bogged down somewhere in China for no appreciable gain.
Never mind the fact that if the US expanded the war to China proper, it would lose its UN mandate for the war, which could lead to some of its allies dropping out. That could be disastrous for the war in Korea.