Like it or not most Southern states didn't freely join anything. They were admitted, and only with the permission of a majority of the existing states through a vote in Congress. Leaving should have required the same.
While I admire Lincoln for making some very tough choices it should be noted that he was the President who gave form to the leftist concept that the Almighty State trumped any and all other concerns including such trivialities as free speech and the right to keep and bear arms.
The poor guys been dead for 142 years and it's amazing at all the nonsense he still gets blamed for.
Why? Admission to the Union is textually committed to Congress by Article IV of the Constitution:
"New States may be admitted by the Congress into this Union; but no new State shall be formed or erected within the Jurisdiction of any other State; nor any State be formed by the Junction of two or more States, or Parts of States, without the Consent of the Legislatures of the States concerned as well as of the Congress."
But it doesn't say anything about states leaving the Union; thus, given the tenth amendment, shouldn't it be the right of every state to leave the Union if it so chooses?
Really? Virginia, North & South Carolina, and Georgia were among the original 13 states. With whose "permission" did they join the Union? Your sense of history is lacking.