Thats quite true the US flew in I think 7 Atomic bombs into the area during the Korean war incase the war got out of hand putting China and perhaps
even Russia in a all out war with the US.
Stalin was helping N Korea alittle but nothing to the extent he could have helped. He didnt want Kim Il-sung to invade in the first place as threat
of getting into a War with the US over Korea was thank god not really worth it for him.
The Korean War could have easily spun out of control and become something akin too WW3