ritual war, n.All

Ritual war (n.) and ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠marriage exchange are the same institution: one makes agreements for the sake of hostility, the other stages hostility for the sake of agreement.