What caused the South Carolina nullification crisis?

Firstly, let’s discuss what ‘nullification’ means in a legal sense, what brought it about, and then lastly move on to the issue concerning South Carolina.
Nullification refers to a US state suspending federal law within its borders. In other words, the state is declaring that its own law and not that of the federal government will apply to actions within the state. Nullification was first addressed by Thomas Jefferson and James Madison in regards the Alien and Sedition Acts passed by then President John Adams in 1798. Jefferson and Madison viewed these bills as an overreach by the federal government into state matters. The principle of nullification gained traction in New England as well as the southern states, particularly regarding state commerce.
Although the principle of nullification was becoming more popular, what brought the issue to the forefront of politics was the Tariff of 1832. The federal government passed the tariff against the protests of many southern states. South Carolina then passed an ordinance of nullification and went so far as to threaten secession from the US if the federal government attempted to collect tariff duties.  
President Andrew Jackson saw this as a direct threat to the legitimacy of the federal government to regulate affairs within its borders. He sent American warships to Charleston and strengthened federal fortifications. Meanwhile, the US Congress passed a Force Bill in 1833 authorizing Jackson to use federal troops to enforce the tariff.
Senator and former Secretary of State Henry Clay took on the role of the Great Compromiser, similar to the one he had during the Missouri Compromise of 1820 that brought Maine into the Union as a free state and Missouri as a slave state. Clay was able to convince Congress to pass the Tariff of 1833 that would reduce the tariff introduced in 1832 over a ten-year period to the tariff level of 1816. South Carolina accepted the deal and repealed its nullification order. However, the state legislature then nullified the Force Bill, perhaps as a way of sending a message to Jackson regarding federal overreach. Jackson ignored this last action by the state allowing for the potentially explosive tariff matter to finally settle down.
South Carolina was very close to seceding and although the other southern states were sympathetic to its cause, none had gone along with nullification. We can see that federal versus states' rights was a problematic issue long before the American Civil War. Instead of a singular event, South Carolina’s nullification crisis is best viewed as just one in a series of events that finally split the country apart in 1861.  
https://avalon.law.yale.edu/19th_century/ordnull.asp

https://www.history.com/topics/early-us/alien-and-sedition-acts

https://www.presidentprofiles.com//Washington-Johnson/Andrew-Jackson-Nullification.html