[Bumping to the top to call attention to a few updates - KMT]
I'd be happy to post and update a roundup of other legal and constitutional historians' commentaries on the ACA case, if brought to my attention. For starters, here are ones by Gerard N. Magliocca, Indiana University-Indianapolis Law, and Stephen Presser, Northwestern Law.
UPDATE: Over at Balkinization, John Witt (Yale Law) has contributed a guest post titled "The Secret History of the Chief Justice’s Obamacare Decision." [KMT]
Under the auspices of the American Historical Association, the historians David T. Beito, Alan Brinkley, and Beatrix Hoffman weigh in on the case here.
Here's an ACA-related post from Ken Kersch (Boston College) at Balkinization: "Research Note: The Postwar Right’s Constitutionalist Anti-Tax Movement." [KMT]
My Georgetown colleague John Mikhail notes historical precursors to Justice Ginsburg's notion of an implied federal power to promote the general welfare, including an address Theodore Roosevelt delivered in 1906.