If you put the Comanche or Assyrians or up as your typical patriarchal society, almost any other organization would yield less violence.

But is 21st century Western Europe a "patriarchy"? Did we already do it, or is it waiting to be done? Are the levels of violence higher or lower than those of, say, 15,000 years ago (before the patriarchal revolution), and how much? What are the error bounds on this estimate?