Agreed: We should do the right thing from the outset, if we can.
A lot of times, the right thing isn't apparent at the outset. Sometimes, it takes extensive study and experience--and trial-and-error--to figure out what the right thing is in a new situation.
On top of that, large and complex institutions like the U.S. military change very slowly. I think this is generally a good thing. I think that in the case of POWs, it's generally a safe interim policy for the military to simply continue with its current methods of dealing with POWs. I think it would be extremely counter-productive to begin dismantling the current system when we have no idea what to replace it with, or how well our new system (which we don't even have, yet) will work.
Also, America being a democracy, the "war on terror" ends when we citizens say it ends. We'll make our decision known most likely over a period of some years, populating the Legislature with politicians who reflect our views and culminating with the election of a President comitted to ending the war. At that point, the American people being what we are, the public outcry for the release of the remaining POWs will be great, and our government will act accordingly.
I expect that there are two things that go on in a camp such as Guantanamo Bay: One, Prisoners of War are detained in accordance with the humanitarian standards laid out in the Geneva Convention and in published military doctrine. Ironically, since World War Two at least, compliance with the humanitarian standards of the Geneva Convention means that the host country invests more in the well-being of its prisoners than it invests in the well-being of its own troops.
Two, Prisoners of War are interrogated by military personnel, to learn any useful tactical or strategic knowledge they might have. I assume the interrogations will range in severity from gentle to harsh; that they will use a mixture of public, commonly accepted techniques and secret, brutal techniques; and that they will have mixed results--some interrogations will yield useful information with little effort, and some will result in excessive torture to no good effect.
For all of this, except the secret torture techniques, there are already many oversight and public access resources. There's Congressional oversight. There's the military's own internal inspectors and standards committees. There's the Red Cross, which has been inspecting Gitmo regularly.
I'm not sure how much more visibility into POW camps you want, or can reasonably expect to get.
Obviously, the military isn't going to reveal all of its interrogation techniques, nor is it going to reveal much of the information it learns from interrogating POWs. As a private citizen, there's not much you can do to audit those things, without grievously jeopardizing the very security your military has set out to preserve.
Instead, you must rely oin certain elected officials and their appointees, who are trusted with our nation's secrets, and who report to us (honestly, we hope) on the status of secrets we should not want them to reveal.
I admit, this isn't a great system, but it's about the best one we have: All other methods would either put the secret power more firmly in the hands of unelected officials over whom we have no authority at all, or else reveal all our strengths and weaknesses to the very people from wh'm we're trying to keep secrets in the first place.