The Fugitive Slaves Act was passed as a federal law. The southern complaint that northern states refused to enforce it is valid from a legal point of view. If northern states are allowed to disregard federal law, why shouldn't the southern states be allowed to do the same?
Apparently you missed the point, some northern states were claiming states' rights in opposition to the Act, but did the South have their back? Oh snap, that's right, the South only squawked states' rights when it served them.
Never was illegal. In fact some northern states threatened to secede over the Fugitive Slaves Act. Kentucky and Virginia threatened to secede over the Alien and Seditions Act.
What do you mean never. Is it in the Constitution? And who cares if a state threatened, what matters is is actually doing it, and none did until 1860.
Moreover, treason is defined as war against the States, i.e. the individual states, not the United States. If anyone is guilty of treason, it's Lincoln.
Treason, Article 3 Section 3: Treason against the United States, shall consist only in levying War against them, or in adhering to their Enemies, giving them Aid and Comfort.
Implying northerners weren't racist. Lincoln wanted to deport blacks to Africa.
Most Northerners were racists is the traditional sense as pretty normal at that time, but that doesn't translate into the very abnormal, revolting racism of abject bondage. Having mildly racist beliefs is not the same as conducting inhuman enslavement. You are bordering on being a slavery apologist by not accepting basic distinctions.
The deifying of Lincoln is the real revisionism of history. The idea that hundreds of thousands should die to consolidate the power of the federal government is repulsive. Asserting that they died to free the slaves when that was nothing more than an afterthought added to justify Lincoln's war is even more repulsive.
Many died to because the South wanted slavery and the North wanted to preserve the Union. Freeing slaves was a political, economic, and militarily wise thing to do at that time and was also a humane and moral thing to do once the fight was on, since it's the main reason the South was batshit crazy and the North no longer had to put up with that embarrassment.
The evidence of how central slavery was to the South's actions is not even debatable. Example: Southern leaders took offense that northern states have denounced as sinful the institution of Slavery and permitted open establishment among them of [abolitionist] societies ... In other words, northern and western states should not have the right to let people assemble and speak freelynot if what they say might threaten slavery. Everything the South did and said had slavery as a central component. Seriously, do we really need to bring in all the ugly quotes from southern leaders right before and during the war that unflinchingly shows their sacred devotion to white superiority and slavery?