Many Americans never thought abortion was fine and acceptable. .
Many Americans never thought slavery was fine and acceptable.
That is the point I was addressing.
More Americans thought it might be unacceptable, but it was necessary. Our morality sometimes gives way to our pragmatism, in how our perceptions are formed. You can see how people believe that abortion is not immoral because it is individual choice... but since when does an individual's choice trump what is morally right or wrong? We ALLOW it, even though we realize it is immoral, for the sake of appeasing a claimed right of choice.
Slavery is very similar in terms of a societal issue, but for different reasons. In 1860, the #1 export crop, and thing the government earned the most in revenues from, was COTTON! They called it King Cotton for a reason. Northern textile tycoons became very wealthy with it, as did exporters and shipping magnets, and the US GOVERNMENT! Our entire economic system was dependent on Cotton, so anything dealing with the production of Cotton, was very sensitive.
As a society, we didn't like slavery, we had made what, at the time, was great strides in moderating our views on slavery. The US had outlawed slave trading, you couldn't travel down to Charleston and pick out slaves from the ships arriving from Africa anymore, that had stopped happening entirely. Technology was coming along, which would have eventually rendered slave labor obsolete, so the days of slavery were numbered. Still, in 1860, much of the cotton production was dependent on slave labor... slaves that had been legally purchased and deemed property by the SCOTUS. It wasn't the plantation owner's fault, he didn't make the rules, he simply made an investment in property to do the labor in his fields, in good faith. Why do you think the Federal government should have the right to turn around and tell him this is not legal and he has no rights to his property?
What if, tomorrow, the Federal government said: We can no longer tolerate pollution from internal combustion, so we are outlawing the internal combustion engine and demanding that everyone turn over their vehicles to the government to be destroyed? From a purely 'moral' standpoint, they can justify this... but does it make this constitutionally right? People say... but that's no fair, slaves were humans! But they weren't 'humans' in 1860, according to the SCOTUS, they were 'property.' The argument was often made, they were NOT humans, they were a sub-human species which were similar to humans. This is shocking and abhorrent to hear today, but that was the prevailing thought in 1860. Save for a few religious leaders who considered them part of humanity and God's creatures, who founded the abolitionist movement.