Akhil Amar's New Article

It's very good.  It actually mentions David Barton (because his controversy is current).  It also stresses something about the attestation clause (In The Year of Our Lord) that I had not, until recently, been aware of. When confronted with the notion that this is God in the Constitution, I would usually note, it's just the way of customarily stating the date, not a statement of constitutional principle.  But even more, it wasn't even written or ratified by the framers.  As Amar writes:

As it turns out—though this fact has until now not been widely understood—the “our Lord” clause is not part of the official legal Constitution. The official Constitution’s text ends just before these extra words of attestation—extra words that in fact were not ratified by various state conventions in 1787-88.