But this is very misleading. Modern people think the northern states abolished slavery because they thought it was immoral and because it was unfair to black people.
A very tiny minority of the Northern public was against slavery because they thought it was immoral. The vast majority of them hated slavery because they saw it as an economic threat to their own wages and income, and also because they hated the idea of associating with black people.
The Northern peoples didn't actually like black people. The "Land of Lincoln" passed all sorts of laws making it illegal for black people to live in Illinois, as well as various other horrible laws regarding how they were treated in that state. Other Northern states did likewise.
To assert that Northern people cared about black people is one of the biggest lies of the Civil War. The vast majority hated them and wanted them kept out of the nation. In fact, much opposition to slavery was based solely on the desire to not have black people in their communities.
So when you say they "cared", don't mislead people as to what it was they actually cared about. What they didn't care about was the misery and suffering of black people. That is a later day fabrication used to justify what the Northern people did to the Southern people.
A lot of what you say is true. But it matters not what reason slavery was outlawed. The fact slavery was illegal in several states. Those people were free men & women. Whether they were liked, disliked, considered equal or hated, does not matter, they were free. Something that was not going to happen in the South.
We had a long discussion with Diogenes about the court decision that freed the slaves in Massachusetts. Those decisions came down because the state had fought for freedom in the Revolution and recognized that slavery was opposed the the principles they had fought for. While the decision was made by judges, the people agreed with the decision. There was no outcry against it.
So much idiocy from Diogenes. Do people really "care" in a loving, solicitous way about those they don't know? Not really. Not then and not now. But they do sometimes try to end oppression and abuses and imposed on other people. They may not want the victims to move in next door, but they sometimes do take action against injustices, and in that more limited sense, they can be said to "care" about what was done to other people.
But none of this fits with Diogenes's polarized and oversimplified view of the world.