Sometimes, nothing else but violence will work, even if the person who has to initiate violence has not had violence used against him. It is possible to smother, oppress, and dominate a person (or a nation) without ever firing a shot in anger. Sometimes a (relatively) small use of violence can prevent a greater one later. Had it not been for the hyper-pacifism among most of the Allied Powers after, WWI, WWII would have been strangled in the cradle.