Marty Lederman has some important background on what Geneva’s Article 3 means, how, before Cheney-Rumsfeld, the United States had adhered to it strictly for fifty years, and how the 9/11 Commission specifically recommended that adherence be restored. Money quote:
At page 380 of its Report, the Commission recommended that the United States “engage its friends to develop a common coalition approach toward the detention and humane treatment of captured terrorists,” and expressly urged the U.S. to “draw upon Article 3 of the Geneva Conventions on the law of armed conflict,” which was “specifically designed for those cases in which the usual laws of war did not apply.” Common Article 3’s minimum standards, reasoned the 9/11 Commission, “are generally accepted throughout the world as customary international law.”
Except for rogue states that refuse to abide by even minimal standards of decent treatment. I.e. Bush’s America.
The Dish 