How do we create a better world?
We should not ask, "Is it morally reprehensible to use force to retaliate against or prevent violence?"
We must ask, "How do we create a world where this question of morality need not be asked, how do we do away with force, violence and fraud from our world?"
A war in any sense must use violence and coercion to take place, no only from the standpoint of the enemy of a state but also against its own citizens who must be stolen from to pay for a war to which they may not agree.