Interestingly, perhaps the biggest irritant to southerners that led them to secede was the ineffective federal enforcement of the fugitive slave laws, which was largely invalidated by northern state enactments.
In a classic example of federalism and states rights, northern states passed laws making enforcement of the federal laws difficult to impossible. Numerous southern states cited these laws in their Declarations of Secession as a reason why they wanted out of the Union.
IOW, prior to the Civil War southern states were demanding expansion of federal power, while northern states were resisting it.
Emphasis bump. It might also be noted that the federal courts were also sympathetic to slave owners in the years leading up to the southern rebellion.