My point is that England was among the first, if not the first, European nation to abolish slavery. They did so before we did, and without a war. Had they defeated us during the Revolution, then due to the Philipsburg declaration slavery would have ended here with our defeat.
If we are going to play the ever popular moralizing over slavery game then lets quit pretending that we have the edge. Britain abolished the Atlantic slave trade the very same year that our Constitution abolished it. And they abolished slavery in their colonies before we abolished it here. Moreover Britain’s navy put a whole lot more energy into shutting down the slave trade than we did. Nothing more complicated than that, other than that falling into the moralizing trap in the first place is a fool’s game.
They used a phased approach and bought the slaves out of bondage. That was not even tried in the US. Our federal government used aggression as the only recourse and didn't even attempt a peace commission.