The previous poster gave no reason for the Chinese control of the rare-earth market, he simply said they did. You didn't contradict that, you simply explained the reasoning behind it, and, in addition, punctuated the point I made at the end of my reply; If we greatly expand electrical motivation, that by necessity requires a vast increase in rare-earth mining (lithium for batteries, neodyminum and samarium for high-strength magnets... heck, even just plain ol' copper mining would have to greatly ramp up.)
And, as you correctly note, such mining tends to be rather "dirty" environmentally.
So the choice is drilling for oil, or mining for ores. We're going to do one or the other. We have to. There is no choice.