" And where abolitionists preached slavery as a violation against the higher law, Southerners angrily countered with their own version of the deity, that it was sanctioned by the Constitution. In the vortex of this debate, once the battle lines were sharply drawn, moderate ground everywhere became hostage to the passions of the two sides. Reason itself had become suspect; mutual tolerance was seen as treachery. Vitriol overcame accommodation. And the slavery issue would not just fade away. "

― Jay Winik , April 1865: The Month That Saved America