I'm more Machiavellian so violence does work you just got to use it tactfully and skillfully. Not burning down cities, looting everything that isn't a book store.

You have to use it as 'a grand gesture', one massive show of force that eliminates not just a lot of your enemies but also those that pay lip service to you (useful idiots) those actively plotting against you and those that move where the breeze blows. Eliminate them all at once and then allow peace because people know how ruthless you can be, they'll prefer to deal with you in ways that don't require force.

You can do this politically speaking too so no need to 'let the bodies hit the floor'.