I don’t think anybody in the South thought slavery was going to continue in perpetuity. The Civil War was about more than just slavery. Everyone knew mechanization was the coming thing.
If you are of the misguided assumption that the Southern businessmen operated in a vacuum and had no interaction with the rest of the country you would be wrong.
If you want to have an argument about just bashing the South that’s fine but the discussion here is really about the fact that in 1861 the US and the world was on the cusp of the industrial revolution and things were changing very quickly. If the Civil War had never happened slavery would stll have been on the way out and fairly quickly.
The Privilege of the Writ of Habeas Corpus shall not be suspended, unless when in Cases of Rebellion or Invasion the public Safety may require it. No Bill of Attainder or ex post facto Law, or law denying or impairing the right of property in negro slaves, shall be passed.
Much of the language of the confederate constitution was taken directly from the US Constitution (see comparison here: http://www.jjmccullough.com/CSA.htm) but there were a few notable exceptions, memorializing the Particular Institution for all eternity (or at least as long as the confederacy lasted) among them.
What were these industrial changes you speak of?
If the Civil War had never happened slavery would stll have been on the way out and fairly quickly.
I'm not aware of any quotes from any Southern leaders prior to or at the beginning of the Civil War that indicates they believed that.
Nice myth for you to believe, but no,they didn't know that then and would not have believed it had you told them. In fact, mechanization of cotton harvesting didn't become practicable until the 1950s. Before that, virtually all cotton was picked by hand.
I first visited Georgia in the early 1960s and there were still plenty of 'share croppers', white and black and still plenty of cotton picked by hand.
No one in the south in 1860 envisioned bringing in a cotton crop without slave labor.