Sure, citizens have a right to rebel against an unjust government. But was the South being treated unfairly enough to justify a rebellion is the question. Most Northerners say no, while most Southerners say yes. Under the constitution, the South had no right to secession. There’s no statement or words in the constitution that explicitly gives the right of secession to any state. Any dissolution of the union would have to be agreed upon by all participants i.e. the states. That obviously didn’t happen. So it was a rebellion....not some sort of legal secession.
“. Under the constitution, the South had no right to secession. “
Nothing in the Constitution says so one way or the other. It is your personal opinion that you state. Common sense and many founding father’s statements, including those of Lincoln, say the people have the right to determine for themselves who will govern them.