As you've said yourself many times, Dennis, it's all a matter of perspective -- or context, if you will. If we expect people to view the South's "peculiar institution" in the context of the times, then we should also expect people to view the wartime decisions of Lincoln and Davis in the perspective of the history of national leaders in time of war.
Ultimately, if it wasn't for both the good and evil things that the presidents, generals and citizens of the North and South did during the Civil War, we wouldn't be who we are today. That, too, is perspective.