I beg to differ with he above comment that States Rights was based on the South's desire to preserve slavery. Although slavery was an issue, States Rights became a burning question primarily over the tariff issue. Tariffs supported Northern industry, but were harmful to the Southern agricultural states which imported manufactured goods from Europe and also sold cotton and other agricultural products there. The issue turned on the relationship between the States and the Federal Government. Thomas Jefferson and James Madison had previously promulgated the argument of state's ability to declare acts of congress unconstitutional within its borders in the Kentucky and Virginia Resolutions. John C. Calhoun echoed this sentiment after the Tariff of 1828, the so called "Tariff " was passed. Southern states argued that Congress's power to pass tariffs was for revenue only, not for regulation, therefore the tariff was unconstitutional. Calhoun (and Jefferson and Madison) believed the right to make that determination belonged to the States. So slavery was not the salient issue; it was the tariff.
Intellectually, the idea of states' rights was based on the idea that the Constitution and the Union was an agreement between sovereign states, not between all the individuals of the country. People who believed this also believed that states had the right to dictate the terms of their involvement in the Union. Because of this, they had the right, for example, to nullify federal laws as South Carolina tried to do in the early 1830s and they had the right to secede, just as the US would have the right to pull out of the UN today.
Practically speaking, the idea of states' rights was all about slavery. The South's demand for states' rights was really based only in their desire to preserve the system of slavery.