Julian Bach argues that there is always the clash between traditional and liberal beliefs about slavery.  He mentions that slavery was “natural and historically universal, but it was vindicated by political, social, and economic expediency.”  Also, he believes that the Southerners consider freedom a privilege or a rank that they have received so they are very unwilling to share that "status" with African-Americans who previously were under their control.  These thoughts of the Southerners confront those of the Northerners who are more experimental and liberal, creating tension between the two regions.   

Bach, Julian S. "The Social Thought of the Old South." The American Journal of Sociology 46.2 (1940): 179-188. <http://www.jstor.org/stable/2769450>.