Another common criticism of anarcho-capitalism that I've seen is that people think that if people have freedom to have the ability to defend themselves, for there to be private armies, than then this will lead to warlords taking over and ancapistan would be warlords constantly at war with each other.

I think ancaps in response have argued that states are kind of like "warlords" and they sometimes go to war with each other, and often are at peace because peace can be mutually beneficial. I guess there's no real guarantee of how much war ancapistan would or wouldn't have, any more than there's that guarantee with states.

What do you think of the "warlord" objection and how do you respond to it?