Maybe because the slave power fought tooth and nail to preserve it when the rising tide of world opinion was everywhere against it.
At a time when the Czar was freeing the slaves, the Richmond Examiner was saying:
"It is all an hallucination to suppose that we are ever going to get rid of slavery, or that it will ever be desirable to do so. It is a thing that we cannot do without;that is righteous, profitable, and permanent, and that belongs to Southern society as inherently, intrinsically, and durably as the white race itself. Southern men should act as if the canopy of heaven were inscribed with a covenant, in letters of fire, that the negro is here, and here forever—is our property, and ours forever—is never to be emancipated—is to be kept hard at work and in rigid subjection all his days."
Walt
Crap. The Czar freed the smurfs, er, serfs.
Walt