[sushshshsh]

I think you have posited interesting ideas about the decisions that small and large groups make about when to engage in conflicts and how to ensure long term survival. I am not sure how true they are in reality, but I can certainly see where you are coming from.

If I put myself into that situation for a moment, as the leader of a small armed group, I can see two options at first. The first option is to go into hiding and potentially die of resource starvation if I am unable to cultivate the things needed to survive on my own (or be killed by outside attackers). The second is to grow bigger and bigger by forcibly and preemptively taking over the other small groups so I can secure my borders so to speak, but going on the offensive can also lead to premature death as well.

As a result I think some hybrid approach is needed, where one goes into hiding in a land so far away and inhospitable that nobody wants to attack, thus there's nobody to fight.