A recent post by history prof Mark R. Cheathem, Nullification, the South, and Historiography, prompted a thought.
It's unfortunate that the doctrines of nullification and secession became entangled with and identified with the defense of slavery. Substantively the doctrines are neither good nor evil. They could be used just as well in support of an end that most of us would consider admirable – to block, for example, a Sedition Act, or federal regulations requiring you to eat a serving of broccoli each day.
This does not mean that the doctrines are clearly correct either. But the unique historical identification of the doctrines with slavery skews all discussions about them and makes it extremely difficult to exchange views about their merits without the discussion promptly descending into accusations and finger-pointing.