The secession papers specifically cite the failure of the federal government to enforce the federal law, which is exactly what I said. You've restated what I said in your second paragraph, which flies in the face of your first paragraph.

Secession was not he reason for secession. Secession was the only issue in which the Confederate states advanced states' rights as an argument supporting their position.

According to OP, apparently because they weren't allowed to?

I answered that question. They wanted to secede because the federal government wasn't enforcing federal law, specifically the escaped slaves act. States were using their own courts and their own legislatures to free slaves, and the federal government was not willing to override states' rights. The states' right to own slaves was not in jeopardy at that time. The only states' right that the secessionists wanted to avail themselves of was the right to secede, which they didn't actually have.

There was nothing indirect about it. The direct reason was slavery. Slavery was federal law. It was not state law in every state, and the Confederate states did not want to stay in the union if the federal government wasn't going to enforce slavery in states that had abolitionist state laws. The federal government was not trying to tell Conferates that they had to free their slaves, so the Confederates were not on the states' rights side of the slavery issue when they attempted to secede. They opposed states rights to abolish slavery.

When they seceded, they used, in part, the argument that states had the right to secede from the union. They did not, and we fought a big war over it.

They seceded because they did not have faith in the union to enforce slavery, which was federal law. There were more government representatives from slave owning states, and there was no risk of abolition prior to their secession.

Those people are confused, understandably, because states' rights was the rallying cry of southern bigots during their opposition to the Civil Rights Movement and desegregation. Bigots don't tend to be the most enlightened or thoughtful people, and this is a topic that trips up even intelligent and informed people.

I'm pretty sure arresting on return and arrests for helping people to leave the state are already happening.

It's certainly close enough that there are preemptive reports asserting that it would be federally illegal: https://www.reuters.com/world/us/us-justice-department-says-constitution-protects-right-travel-abortion-2023-11-09/

The Alabama lawsuits seek to block the state from criminally prosecuting those who facilitate out-of-state travel for an abortion. Alabama Attorney General Steve Marshall has said those who aid travel can be charged with conspiracy if the out-of-state abortion would have been illegal in Alabama.

The best prageru video ever.