Just how are detainees at Guantanamo Bay, Cuba being treated?
We don't know, because the guidelines are classified.
All we do know is that the methods used were 'scaled back', from those previously authorised by US Secretary of Defense Donald Rumsfeld after an investigation revealed objections from US military lawyers, saying they went 'too far'. According to a a senior US military lawyer, it [now?] fully conforms with international law - obviously this has to be taken on trust, or not at all, because the guidelines are 'classified'.
The US Administration has stated that al-Qaeda and Taleban suspects are not subject to the Geneva Conventions - I think I heard Rumsfeld say some months ago that they were being accorded 'most of' the the protections afforded by the Conventions, or something like that - but of course this particular body of international law does not derogate authority to any signatory state a privilege to vary the Geneva Conventions IN ANY WAY and still permit the detaining power concerned the right to state the Conventions are being observed. They either are, or they are not. So the question I have (asked many times before) is - what international law, precisely, is the US Administration claiming it is following?