“...That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form,...”
You can very rarely abolish something with kind thoughts and words. We may all agree that there are natural rights given by the creator, but for most of human history only a small percentage of people enjoyed such rights. The rest were peasants, serfs, or slaves with little to no say in what happened to them.
In this world might does make right. Without winning the revolution by force of arms most of the founding fathers would have been hung as traitors. Sadly not every group that has the might has a good cause and not every group that doesn’t have the might have a bad cause, and vice versa. When viewing these events in history it is up to us to use our brains to make a determination on who was in the right and who wasn’t.
There is no mention of secession in our constitution. No mention at all of any mechanism for a state to leave the union. But it does state that congress has the power “To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions;.”
On top of that Presidents prior to Lincoln had already set the precedent of using power in either words or deeds. First being George Washington when he called out and lead the militia to suppress the Whiskey rebellion. Then later when Andrew Jackson threatened to march down to South Carolina during the nullification crisis of 1832 and hang the leaders that were talking of secession.
The Declaration was only 11 years old when the Constitution was written. It articulates an absolute right to secession. Do you think the founders had forgotten it after 11 years?
Even so, three states specifically assert the right to take back their powers from the Federal government in their ratification statements. They are New York, Virginia (the two most powerful states at that time) and Rhode Island.
No one objected to their inclusion of this language in their ratification statement, and the fact that these three states explicitly stated that secession would always be an option for them indicates that neither they, or anyone else saw the prospect of taking back their power as a contradiction to the US Constitution.
There is quite a lot of proof that the founders always saw secession as ultimately legal, and very little proof that the constitution forbade it.
“To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions;.”
So if you call a tail a leg, it becomes a leg? (to Paraphrase Lincoln's famous quip.)
Secession is not "rebellion." When an entire state votes to leave, calling it "insurrection" is a lie. Calling it "rebellion" is a lie.
Lincoln only called it such to unlock powers he would need to keep the South under control. He literally called a tail a leg, and then locked up anyone who disagreed.