You keep saying this. You really do. But it's not true. The South freaked out about the North's growing population, believing they were eventually going to be outvoted and forced to industrialize. They wanted to keep being who they are, which meant having slaves for sure, and they saw the North as a threat to that. But Lincoln didn't run on a stance to get rid of slavery. He didn't run arguing for blacks as equal humans to whites. He died holding the view of "Slavery is wrong, but..." just like nearly every political figure from that time.
Acting like Lincoln fought the South to free slaves is bogus. Andrew Jackson wanted to invade South Carolina after hearing that Calhoun was arguing for secession, and he was a slave-owner (who had a much more complicated relationship with slavery than most political figures of the time, btb). Lincoln wanted to preserve the Union, plain and simple. Slavery wasn't abolished until eight months after Lincoln's death. Union States like Maryland still had slaves at the end of the Civil War (since the Emancipation Proclamation didn't apply to non-Confederate states).
Simply put, to equate Lee to slavery is ignorant, and a just society shouldn't allow that to become the prevailing view. The Civil War was a very complex period, and it shouldn't be boiled down to the bad, racist South versus the Northern, enlightened liberators. If there's a legacy to be taken from that time is that the country had to really deal with its diverse makeup for the first time. It wasn't nearly the last time it faced that issue, but because of the Civil War, you knew the country was always going to survive it. The only reason why people even have strong feelings against the war is because of what a cluster Reconstruction was and how that pretty much guaranteed that Jim Crow was going to happen. But again, we completely ignore how the Northern Republicans sold Southern blacks down the tube. But where are the folks trying to get the name Hayes High School (the Delaware one) changed?