They didn’t volunteer, they were conscripted. The confederacy passed 3 different conscription laws because they severely lacked manpower. Even then, they had massive trouble with deserters. This is a foolish narrative that revisionists Democrats have tried to pull on you. Be a better pede
The rest of the post’s principle as far as I can tell is that states have a right to secede if they want to. This was hotly debated prior to the civil war, so the discussion is fair game, which is why I didn’t address it.
However, the Supreme Court has consistently interpreted the constitution as an “indestructible” union since 1869 in Texas v White, making it the current constitutional law.