This runs into problems when you try to apply it to groups, and to second/third order effects.

This also, only works where both parties are able to negotiate, capable to negotiate, and are both good actors. Just like in a relationship, you need two people working on it. If one person does not, then all of this good intentions goes out the window.

Say, you have one bad actor. And you negotiate to share water.
When do you kill the other guy? Before, during or after he steals the water you need to live?
It is self defense after, but at that point, you are dying…

And, you will find that the only solution in most cases is to kill narcissists/sociopaths as soon as you recognize they are such. That kinda goes against the nice, simple rules stated above.