a. maybe, but so what? does that mean that we shouldn't fight for the world we want?
b. depends. it's unclear how we got here (what combination of chance, material, psychological, cultural factors, etc), so it's unclear what would allow a similar situation to re-arise.
c. one (or part) of the definitions of government is that it is a body that seeks to have and maintain a monopoly on violence. people would be more able to defend themselves against this (attempt at) monopoly if it weren't the default, the only thing they knew, what they were born into. (i haven't read it yet, but i hear james scotts' book the art of not being governed is good to read along these lines.)