What should one make of the idea that Madison was disavowing the right of unilateral secession when he wrote to Edward Everett, who was a staunch Union man and who would later speak before Lincoln at Gettysburg, that,
“being a compact among the States in their highest sovereign capacity, and constituting the people thereof one people for certain purposes, it cannot be altered or annulled at the will of the States individually.”?
Is unilateral secession annulment of the Constitution?
This certainly is contrary to the position taken by Federalists in the Virginia Ratification Convention. Madison shaded his old position in the context of the Nullification Crisis because he feared secession and knew that contrary to what the Carolinians were saying, protective tariffs were entirely consistent with the original understanding of the Constitution. I explain these matters in James Madison and the Making of America, and I develop them in fuller detail in “A Troublesome Legacy: James Madison and ‘The Principles of ’98,'” Journal of the Early Republic 15 (1995), 569-89.