You could say that but how many times in history has the civilization with the higher tech. conquered a more primitive culture ? Countless. This just human nature and the Spainards were no different than the Koreans immigrants (Japanese) who conquered the Ainu.
One time I can think of that a less tech. society conquered a more advanced one was the fall of the Roman Empire. What bothers me is that it looks like the same think is starting to go on here in the USA with less technical societies (third world/Mexico) conquering a more advanced society ( USA )