Thanks Penny, I just assumed that anyone interested would Goggle William Rawle and find the link.

You comment does point out one thing that more than just one writer before the war argued/taught that Secession of the individual state was legal.

Given the Unenumerated Rights argument that resulted in the 9th Amendment being added to the Bill of Rights during the Constitutional Convention debates, I would say that the "Right of Secession" was more securely established in Jurisprudence that the "Perpetual Union" theory. While these authors stated the desirability of a Perpetual Union they counter that desirability for such a Union against the greater right of the States to secede if it wished to do so.

What is really amazing given the dates that these books were in use, is why there wasn't a much greater uproar made over Andrew Jackson's suppressive actions during the South Carolina Nullification Crisis of 1832?