But now, as it had been during the nullification crisis of 1832, the underlying issue was the North's increasing power. And that power endangered slavery. Secessionists worried that if slavery did not expand into the territories, the black population would stay where it was, bottled up and likely to explode. Fear motivated them. That is to say, racial anxiety was as pervasive as economic anxiety when it came to secession, though it was hard to separate the two, for they were threaded together with the rope that bound secessionists and many Southerners to their land, their way of life, their mint juleps, and their pride of race.
Lincoln's election was thus not so much the cause of secession as its excuse: institutional restraints (read: the federal government) had insulted Southerners, imperiled their way of life, and held them in thrall to Northern financiers who had forced planters to buy goods in a protected market. "It's a revolution!" Judah Benjamin cried -- a "prairie fire," unstoppable, unquenchable.As if in reply, a disconsolate Alexander Stephens observed, "Revolutions are much easier started than controlled." Brenda Wineapple, Ecstatic Nation: Confidence, Crisis, and Compromise, 1848-1877 (2013)