The United States is called United for a reason. The South did violate the Constitution by seceeding; I don't care if they had popular votes in those states or not. Up until the late 1850's the majority of Southerners considered secession to be illegal, which was why no ohter Southern states supported South Carolina during the Nullification Crisis.
Some diehard unreconstructed rebels are just plain unrealistic. The South didn't have the economic means to win the war and got no foreign recognition. I know the Brits gave some aid, but they did so more out of their own self-interest than any real support for the Confederacy (they'd outlawed slavery in 1833). The South's economy was based on slavery; it would have collapsed eventually regardless of what the North might have done. As for the Lincoln bashers, I think any President would have done what Lincoln did to prevent the country from splitting apart.