Grant??? Wow! Looks like you've missed History altogether. But that's beyond the point.

In your reasoning you imply that might is right. That in itself is a morally questionable premise. Would Southern slavers be any better if they won at the time? I don't think so. If anything, they would be even worse. So it doesn't matter that Washington won against the Britain, especially since his victory or defeat has absolutely nothing to do with his position as slave owner.

Furthermore, recent outrage against Confederacy figures is based no upon illegality of the act of secession (I don't see any protests against modern California secessionists) but upon the fact that they were fighting for the continuation of slavery. So, are you saying that in Washington's time slavery was just fine? I mean, if you indeed think it was, just SAY it, loud and clearly--and we'll see, what happens.