It's partly that, but it also serves to fracture and de-motivate the "violent people". A ruler cannot necessarily count on blind obedience from the military and

It's partly that, but it also serves to fracture and de-motivate the "violent people". A ruler cannot necessarily count on blind obedience from the military and the police if they start ordering them to attack their fellow citizens. While some regimes get overthrown by mass uprisings, many more lose power because they either lose support from the security state or create an insurrection inside of it. Of course the lines here are often fuzzy.