Attorney General Alberto Gonzales has sent a letter to the Senate Judiciary Committee following up on his testimony about the NSA domestic surveillance program. The new letter adds a few details and corrects a few potential misimpressions from the AG's live testimony. Among the more interesting tidbits: The NSA surveillance program was authorized by the President very soon after 9/11. Specifically, it had already been authorized by the time the President signed the Patriot Act into law on October 26, 2001.

  Also pretty interesting: The Gonzales letter gives a very strong hint that the initial legal justification for the NSA program within the Executive Branch was mostly a strong Article II claim of inherent power, and that the AUMF argument that the Administration is relying on now did not provide the primary legal basis for the program when it was enacted. See pages 5-6. Given that we now know the NSA program was approved by late October 2001, it seems at least possible (depending on how you read the letter) that the program may have been approved before the AUMF was even passed. That would have required really fast work, as the AUMF was passed about a week after 9/11, but it's at least a possibility.

  What changed that explains the current primary reliance on the AUMF argument? One plausible answer is the Supreme Court's June 2004 decision in Hamdi v. Rumsfeld. Most of the Hamdi opinions are hard to reconcile with the Administration's broader Article II claims. In addition, Justice O'Connor's plurality opinion offered a relatively broad interpretation of the AUMF, making the AUMF arguments more plausible (if, in my mind, ultimately unpersuasive). The shift in legal ground may also explain why the scope of the NSA program and the arguments being made in favor of it don't match very well: It seems that the Administration's arguments in recent weeks weren't the major arguments DOJ was relying on when the program was designed and approved.

  UPDATE: More on this from The Anonymous Liberal.