Whoa people,
Before you start looking to the Korean Police Action for a testament to how a future conflict would end up remember. It was NOT a war. It was a LIMITED action (on our part) that tied the military's hands behind their back. Now I am NOT saying that was wrong. I am just stating there was an artificial limitation on the military.
Rip, you are partially correct in that the allied forces were pushed back to the Chosin Reservoir. You are NOT correct in that the Chinese did NOT kick our prettythanges. They were in turn pushed back to the 38th parallel where the US was stopped by the orders of the Commander in Chief. The Inchon invasion by MacArthur cut the Chinese supply lines and rolled back the lines in a very short time. Truman relieving MacArthur (not without due cause) ended his leadership of the actual fighting and placed the conflict into a stalemate. It should be noted that the majority of the casualties suffered by the US were IN that stalemate period. The fluid battle period were not as costly as merely digging in and fighting over the same freaking few hundred yards for a protracted time.
The introduction of "safe harbors" for the enemy's planes (ala the Yalu River line) was another artificial limitation on the allied options that let the Chinese (and Russian) "helpers" assist the North Korean military. Had the Allied air forces not ben hobbled there would have been no opportunity for the north to build up troops and supplies close to the border of Korea prior to placing them into action farther south.
BTW China used the position that the Chinese troops in Korea were "volunteers" so that they could "maintain" a position that didn't "indicate" an expansionist policy. (And if you believe that.. I have some beach front property for sale in Yuma AZ.) This makes it into a non aggressive action on their part. The Russians only admitted to placing "advisors" in a non combat role helping the North Koreans airforce. Later documents showed they did have a limited combat role during the conflict.
Conflict around Taiwan will have some significant problems for the US. The supply lines will be very long. The Chinese lines very short. The Chinese also know the US has little patience in a protracted conflict. All they have to do is start the conflict then dig in their heels to let it drag on and hope the US will lose the "enthusiasm" for the fighting. If that happens the Chinese (who do take little notice of what their own people think) will simple win by default.
Any conflict will have to be short and decisive for the US to be able to dictate the terms of ending it.
Now that I have dropped all this info, let the debate begin!!
Military strategists speak up.
Mav