That is a good question Alan, but I am not prepared to give a thorough answer. I took PTO this week to work on my final research paper for school. I do recall the politicians and their lobbyists in the Southern States saw the balance of power shifting towards the Free States for many years prior Secession. Just look at the numbers of Free States (yankees) vs. Slave States in 1860. The ascendency of the Lincoln regime and the Republican Party was too much to bear for many Southerners. The firebrands got a lot of mileage from this predicament.