[gbog]

Distance is no weasel word. China historically interfering with Korea or Vietnam is natural as it's neighbors and problems of one side of the border leaks on the other side, and cultural and economical influences are strong. But France or US interfering with Vietnam or Korea make much less sense. The real deep difference in the long span is that Chinese never sailed en masse to the other side of the planet to "propose" (with a gun in the hand) a foreign religion and a different way of life to people which never asked for anything.