Haley blames a 'Democratic plant' for Civil War question that tripped her up

Then, in 1787, many states were unsatisfied with the articles of Confederation, and a Constitutional Convention was called in Philadelphia, creating a new Confederate Constitution. Each state, from 1788 to 1791, individually secededed from the Confederate government and formed a new confederation, also called the United States. Each state agreed to secede from the Articles and join the new government on the explicit understanding that the federal government would only exercise its 19 carefully listed powers, that state independence and sovereignty would be jealously protected, and, in Virginia's notable case, that the right to leave the Union at any time via secession would be protected. The United States was not meant to be a "United STATE" but a European-Union like situation where each state retains full independence

Until the time of the War Between the States, or the Civil War, this was mainstream knowledge. Virginia and Kentucky even refused to obey a federal law signed by John Adams that limited freedom of speech in 1798 via the famous Virginia and Kentucky Resolves, which you can read in full by copying this link into Google: Bill of Rights Institutehttps://billofrightsinstitute.org/primary-sources/virginia-and-kentucky-resolutions

Multiple New England states also nullified more laws, including a military conscription measure passed in 1812, South Carolina nullified a tariff passed in 1832, and Wisconsin even nullified the Fugitive Slave Act in the 1850s. The South gradually became angry though, as the North began to pass blatantly unconstitutional tariffs that benefited New England merchants at the expense of Southern farmers, and grew to completely disregard the constitution by going far beyond the 19 Powers. IN the 1860s, they decided they were done being treated as inferiors by the North and dully exercised their constitutional right of secessions, and, just as every American state had seceeded from the Articles of Confederation in 1781, they left the United States and wrote their own Confederate Constitution. Legally, they were sovereign and independent nations. Admirably, slavery was part of the equation. But five slave states remained in the Union. Abraham Lincoln declared the war a struggle to "Save the Union" having nothing to do with slavery, which he little problem with in the states where it already existed.

But then Abraham Lincoln sent a massive federal army of 75,000 men into Virginia, and the South decided it must assert its constitutional rights by fighting back against the invading army's campaign of murder and terror.

Hope this cleared a lot up.