Traditional societies function on trust. Trust is easy because the family is close knit, and families within each community value each other. It becomes more difficult to survive in the wild when your hut is the only one, and your fire is the only bright light burning at night. Your very survival depends on presence of other families. So you act rationally and value your neighbors.
Modern society does not function on trust. A wife can hide the fact she is seeking divorce because she does not have orgasms under the no-fault divorce rule (I am 99.9% confident this does not apply in my divorce). My point, even within nuclear families, civilization has normalized distrust.
In modern civilization, distrust induces advantageous belligerence, which can be false or true courage.
With loss of trust comes loss of innocence.
I have a post on advantageous belligerence here on the Medium platform. Feel free to check it out.