Right - only politically expedient black people were 2/5ths human is exactly the nuance to bring up in discussions about whether the framers have any credibility 250 years later. You have probably surmised by now that I have less patience with originalists than I do with libertarians for the exact same reasons: all arguments based on originalism are disingenuous at best and deceptive at worst. Simply making one of these arguments means you are humoring the viewpoint of people uninterested in empathy or betterment and are not British purely by stint of opportunism. There's a 250-year history of forgiving the trespasses of the South because at least they didn't serve as another front for British domination but fuckin' hell we fought the Civil War because they obviously wanted to be and the South, and every white mutherfucker they elect, holds dear to their bosom the conviction that they're better than everybody else therefore their rights count more than everybody else and every time one of these "republic not democracy" discussions comes up it's all about a sore loser saying "I have a get-out-of-jail-free card because your ancestors needed mine AND YOU STILL OWE ME." And fuck them. And fuck their arguments. And don't pretend that their basis in fact gives them any grounding in logic or morality.
I don't forgive any of the trespasses of the South. But imagine an alternate history where the 3/5ths compromise didn't exist. The North would have been dominated by the South in every election, because slaves were a majority in a number of slave states. Obviously it's an impossible counterfactual run, but things probably would have been worse, not better. But maybe not. It's also possible that the situation would have gotten untenable more quickly, and the system would have fixed itself.
You mean one where the north said "you know fukkit it's been four years and you guys are assholes and this is a dumb idea so fuck off until you can come back with something reasonable?" The Revolutionary War lasted seven years. The Constitutional Convention was four years later. The 3/5ths rule was debated for a fuckin' month. Congress spent ten times as long on Benghazi as it did on how human Blacks are. Imagine an alternate history where the minority population of the South was treated to minority representation and fuckin' slavery ended up abolished without a fucking war.But imagine an alternate history where the 3/5ths compromise didn't exist.