Language, or a lack of a discernible written language, has been utilized to demonize certain populations. Its built upon the idea that they are heathens mind you, but its still part of the process by which humans can be turned into animals by oppressors, who in turn justify their elimination of those peoples through war
And yes, I do tend to think that we would be better off without religion or at least a different form of religious belief, but I'm not necessarily anti-religious. My point is merely that we should never underestimate humanity's ability to find reasons to hate one another. We're quite advanced in that regard