Andrew Campbell

I don't know but I can see that is the question/issue!
Fighting at this level has been obsolete since we started farming and living in towns but we could stand it because it wasn't everyone, all places, all the time.
Now it is just one of the half-dozen reasons we can't live as we do for much more than 20 or 30 years. (Presumably we will change, find new sources of energy, etc. but we will have to solve all the fatal-to-civilization issues before they come due, avoidance of nuclear war, e.g...)