He was not the first, nor was he the most recent to make this observation, and in spite of his reputation here in the south, he was not even the most ruthless of American Civil War General Officers.
Civil War is a particular hell. When you can remove yourself from the "other," make them out to be "bad" and you "good," it makes the killing easier on the story.
It is even better when you can get your clients to fight each other, and you can sit back and claim "advisory" status, or even better, "observer" or "peacekeeper."
When you can hide the truth from your base, and keep them riled up for more, you can do anything.
Are we prepared to prevent that?