Japan and Taiwan are the only ones I can think of at the moment. Japan's population wouldn't tolerate a massive US military presence beyond what we've already got on their soil, and China wouldn't tolerate us putting any large numbers of troops of equipment on or near Taiwan.
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My point exactly. In spite of the other poster's contention that: "We have plenty of partners in Asia who would love to have our protection and American dollars. Screw the S. Koreans!!" there are no other PacRim countries to which we can move these forces.
As for his: "Screw the S. Koreans!!" let's be kind and assume that he is ignorant of the ROK's support for us in Viet Nam and Iraq.
"and China wouldn't tolerate us putting any large numbers of troops of equipment on or near Taiwan."
Wow, we have some real fear of China on here. I respect there abilities but what exactly would China do? They can't project force anywhere except for possibly Taiwan...and they would lose horribly there in a naval and air battle with US forces.