Apparently they do not understand what federalism means and reject the authority of those who do: Hamilton and Madison.
They were very knowledgable about the document they'd helped produce and knew all the reasoning of the convention and the Framers, but at the end of the day, they were still advocates for a point of view within the convention, from which almost all the people who disagreed with them had either been excluded or had decamped in disapproval.
Furthermore, The Federalist does not deal comprehensively with the Articles of Amendment demanded by the Antifederalists and public opinion: and it was here that Madison, I read in The Antifederalists, began to see the dangers to personal liberty and the potential strength of the government he had helped Hamilton create, and began his migration over to the Democratic Republican ranks, taking some Federalists with him.
The Amendments of the Bill of Rights substantively altered both the content and the nature of the Constitution itself in ways demanded by the American people before they would ratify it, and the Federalists acceded in order to get the document agreed to.
As amended, the Constitution contained many more safeguards and many more points at which power of perpetual consent was distributed back to the People in the jury box, the polling place, and the ranks of the Militia.
And it reserved all nonenumerated rights and powers not specifically granted to the United States Government to the States or to the People. Which is precisely what you National Greatness power junkies and your liberal pals have been trying to break down ever since, to make the People your prey.
He then proceeded to destroy the idea of "secession at will."
Of course the neo-confederates reject Madison and Hamilton. They were key proponents of American nationalism - something the neo-confederates despise.