Convinced that a Republican administration would attempt to undermine slavery by appointing antislavery judges, postmasters, military officers, and other officials, a secession convention in South Carolina voted unanimously to secede from the Union on December 20, 1860. The convention issued a declaration in which it attempted to justify its decision. Drawing on arguments developed by John C. Calhoun, the convention held that the states were sovereign entities that could leave the Union as freely as they joined. Among the many indictments of the northern states and people, nothing seems more central than the issue of trust with respect to the capture and return of fugitive slaves.

James L. Petigru (1789-1863), a staunch South Carolina unionist, reportedly responded to the Palmetto State's actions by saying that his state was too small for a country and too large for an insane asylum.