First, all that data on tariff debates and farmer v. factory worker is, indeed, not the stuff of civil war. The main difference between north and south, the one that led the nation to war, was slavery. The north did not want it to spread to the new western states being created, and the south did. The south fought federal attempts to ban slavery in the west, using the states’ rights argument. Each state has the right to decide for itself whether it will be slave or free, the south said; any federal attempt to ban slavery outright is illegal.

So all the vague talk of the federal government interfering in “state government” or “state policy” sharpens up considerably when you face the fact that the only “policy” at stake was slavery. Slavery made north and south different—and enemies: “On the subject of slavery, the North and South… are not only two Peoples, but they are rival, hostile Peoples,” said the editor of the Charleston Mercury in 1858. [McPherson, 11]

But the southern states were quite willing to interfere with northern state policy, as southern Congress members passed fugitive slave laws that allowed the federal government to go into northern states that had passed anti-slavery laws and personal liberty laws and force those states to hand over people identified as escaped slaves. The fugitive slave laws also allowed southern slaveholders to bring enslaved people into free states without punishment, and forced northern citizens to help slave catchers.

When northern states complained about their personal liberty laws being violated, the southern-majority Supreme Court reminded them that national law outranked state law, and national law had a mandate to protect slavery. Southerners in Congress also imposed a gag rule in the 1830s which disallowed antislavery petitions from northern states to be presented to Congress. [Ibid., 9]  So states’ rights were not so sacred for the south when it came to slavery, and the south hotly demanded that the federal government override northern states’ rights to outlaw slavery in their own states.

That’s why Lincoln’s election to the presidency caused secession and civil war. For 49 of the 72 years in the period 1789 to 1861, the American president had been a southern slaveholder. Now a northerner whose party was created expressly to stop the spread of slavery was president, and the deep south panicked. South Carolina went first, and its secession convention stated that with Lincoln as president, “the Slaveholding States will no longer have the power of self-government, or self-protection, and the Federal Government will have become their enemy.” [Ibid., 7-8, 11]

Note that it’s the slaveholding states losing their independence that is the last straw; when it was non-slaveholding states whose rights were violated, the south was okay with that.

Lincoln’s election not only meant the end of slavery, in the south’s opinion, but was the final nail in the coffin of the two-party system, and the party unity, that had dominated American politics in the 1800s. From 1787 to 1860, the nation was involved in a debate over slavery. That debate was contained by the party system. When that system fell apart, the debate could no longer be contained, or kept contained within the political system.

Few Americans today would recognize the death of the Whig party as a major contributor to civil war, but it was. In the next post, we’ll see why.