If you investigate you will find a long line of supreme court decisions, prior to the civil war about the nature of the constitution and the relationship of the states to the federal government that show secession at will is unconstitutional.
You can also look at the proclamation President Jackson issued during the nullification crisis, which was written with the Attorney General of the United States, which stated secession was nothing more than revolution.
Or perhaps look at the letter James Madison, the father of the constitution, wrote to Nicholas Trist, in which he stated - "
It is high time that the claim to secede at will should be put down by the public opinion; and I shall be glad to see the task commenced by one who understands the subject."
“James Madison to Nicholas P. Trist, 23 December 1832,” Founders Online, National Archives, https://teachingamericanhistory.org/pcuw. Dr. Sir, I have received yours of the 19th, inclosing some of the South Carolina papers. There […]
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