The reference was not to compare Cars to Slaves, But property rights to property right.
When we talk about the slavery we get blinded by the injection of "Morality" into the issue.
Law and Morality should be two things which should be mixed very carefully, like mixing Nitroglycerine. The example left to history caused by the War is that if I feel morally outraged by an issue, I have the right to talk actions against that Outrage even if it is protected by law.
For instance if I followed the example of John Brown, hero of the abolishionist, I would not be constrained to use his tactics against Roe vs Wade avocates. That is a morality issue which many people feel strongly about. Should those opposed to Roe Vs Wade institute a war because we feel that Supreme Court ruling which established a Law of the land is morally wrong?
What is Law? It is the rules by which people govern themselves. Law permits some things and it forbids others. But laws are usually arrived at by the consent of the majority of the people.
Yes, Slavery was a bad thing, and yes it should hae been abolished. But not by the method which was preferred by such radicals as John Brown. It should have been abolished by the rule of law. The failure to follow that rule of law is what "CAUSED" the War for Southern Independence.
Every state had the right to abolish slavery within its own borders. And that was NOT an impossible objective. In Fact it was the radical abolishionist that killed most of those efforts. And the mess that was left behind by the aftermath of the war is still effecting our society today.
The 13th Amendment did nothing for the ex-slaves except set them free. It addressed none of the problems of those persons that the southern legislators were trying to address. Those ex-slaves became outcast to both the northerner and the southerner equally.
And that is what you defend when you claim that the war was fought just over slavery. You defend not only the freeing of those slaves but the treatment and protection that the federal government gave them after the war was over.
It was not a Confederate Supreme Court which established segregation it was a UNITED STATES Supreme Court which ruled in the Plessey Case that Segregation was a reasonable course of dealing with these problems. It was the United States Congress which failed to pass Civil Rights legislation until 1964 at the prompting of a southerner Lyndon B. Johnson.