There's more evidence. At the 1787 constitutional convention, a proposal was made to allow the federal government to suppress a seceding state. James Madison, the father of our constitution, rejected it, saying: "A Union of the States containing such an ingredient seemed to provide for its own destruction. The use of force against a State would look more like a declaration of war than an infliction of punishment and would probably be considered by the party attacked as a dissolution of all previous compacts by which it might be bound."
Professor Thomas DiLorenzo, in his revised "The Real Lincoln," provides abundant evidence in the forms of quotations from our Founders and numerous newspaper accounts that prove that Americans always took the right of secession for granted. Plus, secession was not an idea that had its origins in the South. Infuriated by Thomas Jefferson's Louisiana Purchase, in 1803, the first secessionist movement started in New York, Massachusetts, Connecticut and other New England states.
Every single bit of evidence shows that states have a right to secede. There's absolutely nothing in the Constitution that prohibits secession. What stops secession is the brute force of a mighty federal government, as witnessed by the costly War of 1861. Only one thing good came out of that war. It eliminated slavery. It's had a devastating legacy for future generations of Americans, in that since the issue of secession was brutally settled, the federal government is free to run roughshod over the safeguards envisioned by the Framers, namely the Ninth and Tenth Amendments.
There's little to suggest that the same brutality wouldn't be encountered if secession were tried again, as one writer cautioned: If New Hampshire seceded, massive troops along with today's deadly modern military equipment would be on its soil before lunch.