You made no such differentiation. You argued that the mere possibility that the US, operating under its constitution, would use the political process to eliminate slavery (presumably once the western states came into the Union) justified the south's fight to succeed, because that would destroy their agricultural economy. That necessarily implies that you believed that the South both needed slavery and was entitled to retain the institution of slavery as long as it wished to, and that any effort by the nation as a whole to eliminate it would be illegitimate, wrong and a basis for war.
That is even farther than those who claim it was all about state's rights usually go. You posit that slavery was essential to the south, and the south was justified to defend slavery, not just the principle of states' rights.
You are sick.
Slavery can be understood as an institution that had existed throughout human history, and which had come to be prevalent in the south as a result of certain economic policies out of London, labor needs in a sparsely settled colony, and a market run by Arab traders. It can be explained, and our ancestors can be excused for being products of their time and age, but by 1860, in a civilized society, everyone with any sense of morality knew that slavery was a wrong that had to be phased out in some way. Hell, they knew that in 1776 and in 1789, they just didn't want to face the fight yet, and thought they could put it off a few decades. They thought that in 1820, too. The north knew it was wrong, and hoped to get it solved eventually; the south knew it was wrong and so started coming up with excuses and justifications so that they could sleep at night. They dehumanized themselves as well as their slaves in order to live with it.
By 1860, it could be stomached no longer. Enough was enough. Republicans did not pursue immediate elimination of slavery, they just didn't want it extended. Nothing in the constitution required slavery to be extended into territories, that was a political battle that Republicans were winning. Rather than lose under the rules set forth in the Constitution, the South said no thanks, it would pull out of the Union instead.
The right to secede as a theoretical proposition is debatable, and there are lengthy arguments on both sides, which have been well-written in this thread. What is not debatable among rational people is that Lincoln's decision to fight to preserve the Union, to declare that there is no right to secede, to defeat the southern confederacy, and in the process eliminate slavery as an institution, was the right decision as a practical matter and in the end saved this entire nation and its soul. We would not be a strong, unified nation that could have defeated the Kaiser, the Nazis and the Soviets had this issue not been resolved and had the Union not been preserved. (I have written elsewhere how I believe it likely that the Continental US would now be at least 3 or 4 balkanized states, with a history of war and rivalry, and the technological and economic progress we have made during this time would be significantly set back.)
To suggest that the institution of slavery not only could have, but should have, continued indefinitely into the future reflects a depravity and lack of empathy that can only be characterized as evil. If a professed love of states' rights resulted in 30,000 witches being hanged every year, or the enslavement of all Indians, or the gassing of all Jews or the serfdom of all Scotch-Irish, it would have been no less evil and no less deserving of extinction.
People who grew up with slavery, and in an environment where it was propagandized can have the excuse of not knowing better. You do not. It's been 150 years! I wish we could transport your kind back in time and put you under the lash. Then extend that existence for another 50 or more years. Then extend it to your children and then to your grandchildren. We cannot, so instead, all we can do is point out your ignorance and vileness, and keep your kind from having sway anywhere ever again. You disgust me.
Yeah, so instead of that alternate history, we are now looking at it as a likely near-future.
Yep. It's a concept called sovereignty of the States.
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You posit that slavery was essential to the south, and the south was justified to defend slavery, not just the principle of states' rights.
Right again.
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You are sick.
Whatever
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To suggest that the institution of slavery not only could have, but should have, continued indefinitely into the future reflects a depravity and lack of empathy that can only be characterized as evil.
To remain in the Constitutional confines, slavery should have existed until the States decided for themselves that it should not.
Do you believe the Constitution to be 'evil'?
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You disgust me.
Well, people who have so little emotional control that they cannot stop emoting long enough to look at the facts of the situation disgust me, so I guess we're even.
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It is the mark of an educated mind to be able to entertain a thought without accepting it.
Aristotle