Baron Max said:
Take a moment and ask yourself; "If no one was ever killed throughout history, how many people would be on Earth now?" It's staggering to contemplate.
Nature has its ways. And that means that there will always be a natural disposition arising with some statistical predictability that will come to violence with other entities. We can never entirely eliminate violence from humanity. To the other, even a completely rational body social would eventually be tempered by natural elements. We are part of nature, and cannot conquer it outright.
The natural inevitability of a Hannibal Lecter or Gary Lee Ridgway does not license or excuse the result. The only simple solutions are themselves violent and temporary, and of dubious rationale.
To use an illustrative notion: there are, literally, thousands, perhaps a hundred thousand, "date" rapes on college campuses each year. Among that ghastly number is a proportion, at this point utterly unknown, that could have been averted according to different social conditioning. As with murders and wars: it is only for certain presuppositions that most wars and murders happen.
Even if humanity manages to fix all of these mistaken ideas that eventually lead to violence, nature will still provide us with certain baseline violence.
And if we prosper too greatly too quickly in a newfound understanding and enlightenment, we will certainly be vulnerable the next time the planet decides to cull the human herd.
Nature ought to be enough to deal with. Ideological violence is illogical; passionate violence is illogical. Only sinister violence is logical, but only unto itself.
So why shouldn't we sack all that, and deal with the Universe? It's awfully big, after all. There's a lot to do, and who knows? Maybe we'll get our violence fix wrestling in a species-take-all battle-royale against vampiric strawberry gummi-worms from somewhere in the northeast quadrant of Andromeda. There comes a time when cutting down the evil worms is as essential as destroying the collision-bound comet, but why not let nature dictate? It's a stubborn will that holds wars and kills for love just because we're bored and boring.