In 1833, Mr. Madison spoke much more directly...
Probably because he was offering a private, rather than a public opinion. He had no need to consider whether said opinion was consistent with the written, public opinions that he had offered when 'selling' the Constitution to the justifiably cautious people of the several States (please see The Federalist Papers), and he did not even have to conform to the written, public opinions he offered in the Virginia Resolutions, and his Report on the Virginia Resolutions (links at my FR home page).
You know what? When it comes to public policy, private disclaimers bear no weight, whatsoever, in my opinion...
Madison's statement always leads to the forever unanswered question of what the intolerable abuses were in 1860 which lead to secession.
As Mr. Madison & Mr. Jefferson suggested in their public writings before the turn of the century, it was up to the individual States, as parties to the constitutional compact, to determine if and when intolerable abuses had occurred:
...to this [constitutional] compact each State acceded as a State, and is an integral party, its co-States forming, as to itself, the other party: that the [federal] government created by this compact was not made the exclusive or final judge of the extent of the powers delegated to itself; since that would have made its discretion, and not the Constitution, the measure of its powers; but that, as in all other cases of compact among powers having no common judge, each [State as a] party has an equal right to judge for itself, as well of infractions as of the mode and measure of redress.
- Thomas Jefferson, Kentucky Resolutions, 1798
The illogical suggestion that the federal government (via the federal judiciary) was the only proper judge regarding the existence and 'tolerability'of federal abuses was disposed of by Mr. Madison as well, in his Report on the Virginia Resolutions...
By that logic, nothing he ever said before 1809 and after 1817 bear any weight either. Nor do anything Washington, Jefferson or any of the founders have to say when they were not in office and making public declarations.
But if you care to close your eyes to a not so private declaration from the man who was the most influential of the men who crafted the Constitution, please don't allow me to take the blinders off your eyes and your hands off your ears. Enjoy your myth.
But I have no doubt that if Mr. Madison were with us today, he would tell you your formula for anarchy (i.e. Unilateral Secession) has no place in the Constitution.
Madison had no use for either Democracy nor Anarchy. He belived in Liberty under Law.