Actually, there was no income tax in the antebellum United States and major source of government revenue were tariffs on imported goods. These tariffs hit the South harder than the North because the South imported manufactured goods. The income generated from tariffs, on the other hand, was often used for internal improvements in the North. In earlier decades of the nineteenth century various Southern states groused about this and threatened secession, but it was only the perceived threat of the non-abolitionist Lincoln that spurned Southern statesmen to actually leave the Union.