I personally agree with Truman's refusal to use nuclear weapons against China in the Korean War. From a humanitarian point of view, it was going to be an even bigger catastrophe than what happened in Japan, as China had much more people, so a nuclear intervention would have meant death to millions of people, mostly innocent ones. From tactical point of view, it was also a bad move, because the Chinese would have probably not given up and would have seek revenge. Also, they were backed and allied by the Soviet Union. A nuclear usage would have meant an open war with the Soviets, and that was the last thing that the United States wanted, as they didn't had any significant advantage against the Soviets.
