During the War of Resistance Against Japan, MacArthur used leap-frog tactics to conquer Japanese-occupied islands one after another and approach the Japanese mainland, liberating many countries in the Pacific and making great contributions, so he was very arrogant. The Korean War became famous all over the world with the Incheon landing. Truman did not want a war with China, and MacArthur promised that China would not send troops. As a result, China sent troops to defeat the US military one after another. MacArthur strongly encouraged all-out war with China, including bombing China with atomic bombs. Truman knew very well that the Soviet Union wanted China to compete with the United States in order to benefit from it, so he fell into the Soviet Union's trap for an all-out war with China. Therefore, Truman advocated limited war, which created a sharp conflict with MacArthur. Because MacArthur insisted on his own opinions and could not control himself, Truman decisively dismissed MacArthur in order to ensure the highest strategic interests of the United States. After that, the United States reversed the battlefield situation. Instead of taking advantage of the victory to attack, it took the initiative to negotiate peace in order to get rid of the unfavorable strategic situation.