YES, I KNOW THAT! BUT THEY JUSTIFIED IT AS A NATURAL RIGHT, MEANING IT CAN BE USED FOR SECESSION TOO!
When they did it, it was rebellion. They founded a nation on the right to independence. Thereafter seeking independence was not rebellion in this nation. It was in accordance with the fundamental principle upon which this same nation was founded.
NO, there is a natural right of revolution there is no natural right to secession. The natural right to revolution is an appeal to arms, war. Secession is a legal process to withdraw from a union, a legal process that is nowhere in our constitution no matter what the southern rebels claimed.