If violence never settles anything, then why do we have armed forces and police forces that are deputized to use violence to keep the peace.
Police forces are not deputised to use violence. They will try other courses of action first. And even so, using violence as a means to settle things can't be done as they aren't jury and judge.
As for the armed forces, the defence should be the first priority, otherwise it would be no different than an attacker using gratuitous violence.