It took centuries, but consistent law enforcement with capital punishment did the job…

One of the effective altruist policies was Europe's turn in the late middle ages towards executing criminals.
Homicide rate plummeted. The pool of violent men dried up.
Effective long-termist altruism making the life of succeeding generations far better. pic.twitter.com/c5dz8KWo5D

— Whyvert (@whyvert) September 1, 2022

Former NY Times science writer Nicholas Wade explored this process of weeding out violent genes in his book, A Troublesome Inheritance. Are we due for another round?