> find the notion that humans can be more or less inhumane troubling

You aren't going to "fix" human nature. At least not without eugenics and execution of those who don't think "right". Saying we should be humane and cooperate with each other doesn't cut it. It's as much a pipe dream as anarchism. Although I agree with that philosophy it's never gonna work with humans. High number of sociopaths, prison experiments, the us vs attitude that permeates must all human social constructs, preponderance of human history is the proof. Humans are just too shitty to have nice things.