I've heard theorizing that one reason early North American Indian wars were so disastrous for Injuns because they did not expect Europeans to be so hellbent and dead serious about it. Indians expected maybe a bit of back and forth raiding, pillaging and captive ransoming, and then talking about peace and stopping fighting, but European settlers did not fight like that. They actually did anything they could to eliminate the immediate native threat permanently even if it took multi-year campaigning.