China is a developing country that saves too much, and the United States is a developed country that spends too much. The result is a big trade gap. Does something have to give? Yes. But it's not clear when that will happen, and in the meantime both economies are performing pretty well.
Korea's consumption growth is currently very much dependent on sentiment and unanticipated wealth gains, leading to concerns about the sustainability of consumption recovery.
Taiwan-China relations will be peaceful for a long time to come,