>You're ascribing with morality (a human construct) or are diminishing (it's actually constructive) a natural and productive act that supports virtually all life on the planet.
I'm not sure what you thought I wrote but it's the opposite of what I outlined. My whole argument is indeed that morals are indeed a human construct, so that if someone laments the amount of violence, they should realize that to be able to make such a complaint you already need to have arrived to a point where avoiding violence has granted you evolutionary advantages and thus been selected for to some extent, hence making the question a closed loop. Otherwise, the question would not even be conceivable to our minds.
>I don't know who thinks that humans value nonviolence but they clearly don't read the news.
Just because we engage in violence very frequently doesn't mean it is not valued. There are many different evolutionary pressures coexisting together. At the largest end of the scale, having a less violent society is very much an evolutionary advantage, otherwise we would not have an ingrained sense of fairness, the notion of morality, or as you mentioned the desire to inflict normative violence if that standard of fairness is violated by another individual. These emotions and constructs exist because they bring an advantage, and they do ironically bring on a state of lesser violence through the applied threat of violence.
>a natural and productive act that supports virtually all life on the planet. To escape it we would need to escape nature itself.
Violence doesn't have a special status in the sense that it will be productive in any environment. Just like any other trait, if the conditions change to a sufficient extent, it will become obsolete. It's only positive due to the way things are currently working. We're by definition part of nature so we can't escape it, but that doesn't mean nature will necessarily remain the way it has been in the past.