The US should not miscalculate as they did in 1950 in the Korean War.
Kuleana
What do you mean by miscalculate as they did in 1950 in the Korean War? This was a very delicate situation at the time that involved the US and the Soviets. The big concern for the US was the Soviets, not the Chinese.
Since the beginning of the 20th century, Korea had been part of the Japanese empire, and North and South was divided at the 38th parallel as a result of a post WWII agreement between the Soviets and United States. Soviet backed DPRK soldiers were the aggressors who rolled into Seoul with about $75,000 soldiers, and that's when we got involved. I agree that we could have done more to end this war sooner if that's what you mean but our involvement in some capacity was inevitable.
In April 1950, a National Security Council report (NSC-68) had recommended that the United States use military force to “contain” communist expansionism anywhere it seemed to be occurring, “regardless of the intrinsic strategic or economic value of the lands in question.” Nonintervention was not considered an option by many top decision makers. At the time it was all about not allowing the expansion of Communism.
At first, the war was a defensive one -- a war to get the communists out of South Korea, and it went badly for the Allies. By the end of the summer of 1950, President Truman and General Douglas MacArthur (Commander in Charge of the Asian theater) had decided on a new strategy. Now, for the Allies, the Korean War was an offensive one: It was a war to “liberate” the North from the communists. Initially, this new strategy was a success. An amphibious assault at Inchon pushed the North Koreans out of Seoul and back to their side of the 38th parallel. But as American troops crossed the boundary and headed north toward the Yalu River, the border between North Korea and Communist China, the Chinese started to worry about protecting themselves from what they called “armed aggression against Chinese territory.” Chinese leader Mao Zedong sent troops to North Korea and warned the US to keep away from the Yalu boundary unless it wanted full-scale war.
This was something that President Truman and his advisers decidedly did not want: They were sure that such a war would lead to Soviet aggression in Europe, the deployment of atomic weapons and millions of senseless deaths. To General MacArthur, however, anything short of this wider war represented “appeasement,” an unacceptable knuckling under to the communists.
Possibly this is another part you may have been referring to but MacArthur was fired as a result: As President Truman looked for a way to prevent war with the Chinese, MacArthur did all he could to provoke it. Finally, in March 1951, he sent a letter to Joseph Martin, a House Republican leader who shared MacArthur’s support for declaring all-out war on China–and who could be counted upon to leak the letter to the press. “There is,” MacArthur wrote, “no substitute for victory” against international communism. For Truman, this letter was the last straw. On April 11, the president fired the general for insubordination. (REF: History - Korean War)