That tariffs - by which I refer to U.S. tariffs on goods imported into the U.S. - were a major motive behind secession is acknowledged by even such authors as James McPherson who is now a major propagandist for the "Northern point of view", (see his recent NYT revue of "The Reel History). So I find it difficult to take seriously your characterization of it as a minor irritant, or of the southern reaction to it as irrational.
As I said in my post 301 above, the south was in a position where it , of necessity, exported to Europe and England. Of necessity it in turn imported goods from them. (Not all luxury goods either. In spite of some cloth and clothing manufacture in the Northeast, in the period prior to 1861 cloth and clothing were a significant component of U.S. imports.) This made them sitting ducks for the Northern dominated governments tariff policies, used against the South as a revenue raising means, not as a protection measure. See the newspaper editorial in my post 305, the source for that contains more in the same vein.
Unfortunately, the sources that I have at hand are light on details such as tariff rates and amounts of revenue produced by these tariffs on southern imports. I will try to get some of these details, and, perhaps, get back to you.
"It is false to say that tariffs were even a minor irritant, or cause of the war."
That statement is false. As for your earlier statement that there is no right of secession in the constitution, (which you immediately, unwittingly, declare a fiction) that may be true. However, the existence of the right doesn't depend on its being in the constitution. The constitution does not and cannot grant rights, they pre-exist it and can only be asserted in the constitution, as in the bill if rights.
"The next evil that my friend complained of, was the Tariff. Well, let us look at that for a moment. About the time I commenced noticing public matters, this question was agitating the country almost as fearfully as the Slave question now is. In 1832, when I was in college, South Carolina was ready to nullify or secede from the Union on this account. And what have we seen? The tariff no longer distracts the public councils. Reason has triumphed. The present tariff was voted for by Massachusetts and South Carolina. The lion and the lamb lay down together-- every man in the Senate and House from Massachusetts and South Carolina, I think, voted for it, as did my honorable friend himself. And if it be true, to use the figure of speech of my honorable friend, that every man in the North, that works in iron and brass and wood, has his muscle strengthened by the protection of the government, that stimulant was given by his vote, and I believe every other Southern man. So we ought not to complain of that...Yes, and Massachusetts, with unanimity, voted with the South to lessen them, and they were made just as low as Southern men asked them to be, and those are the rates they are now at." - Alexander Stephens, November 1860
Apparently even your own Vice President-to-be felt that tariffs were a non-issue.