To use force in retaliation — in self-defense against those who initiate it — is not a moral option, but a moral requirement. A moral man has nothing to gain when a man tries to kill him, but he has much to lose if he does not defend himself. The use of force, in and of itself, is not evil — but to initiate (start) force is. Contrary to the doctrines of the pacifists, using force in self-defense is a good.
Any man (or group of men) who initiates force against others is a dictator — a monster — and should be treated as such, to the extent he initiates force.