It was our right under the constitution. The constitution is a free association of individual states. It is not meant to be a death pact. Unfortunately, Lincoln didn’t see it that way and so it is now interpreted by many as a death pact.
What was their right? The right to secede? So the whole war was about we can secede and you can’t stop us? There was no reason to secede, it was just an experiment?
http://www.freerepublic.com/focus/f-news/2480723/posts
The link is to a previous discussion on this topic.
It’s good to see there are others (such as yourself) who have actually studied our history instead of sole reliance on “what we were taught in school.”