The same nitwits over at Lewrockwell.com (we're in Year 3 of the Y2K crisis, according to them) also insist that Lincoln was pro-slavery because he pledged to keep the Union intact rather than abolish slavery. Lincoln made that pledge because he knew that he couldn't get elected otherwise, and if the South left the Union, then all hope of freeing the slaves would be lost for generations to come.
Not really. The most profitable decades of cotton-growing were in the later 1900s, long after the war. Share-cropping was actually a more profitable (from an income vs. expenses standpoint) way to exploit the land.
The real trouble was that southerners had for decades been investing their capital in slaves, till their total value exceeded that of all the land (not including buildings) in the South. At abolition, all this capital just vanished. How do you think Americans today would react to the notion that some group was planning to confiscate something like 1/3 of its accumulated wealth?
The other two big contributors to southern resistance to abolition were an often sincere belief that it was really in the best interests of the slaves themselves, and a repugnance for the social equality abolition would have implied. Southerners had no problem with close, even intimate contact with blacks. No objection to blacks cooking and serving their food. Many had no trouble sleeping with blacks. But most would have objected violently if a black had sat down to table with them.