Well, I certainly hope these prisoners were sometimes interrogated and I would think that it would be far more productive to do that away from other detainees and normal routine of the prison.
Hauling them all in during a war and letting them sit around in cells without asking them anything would seem kind of silly on our part, wouldn't it?
Yep. I'd be far more distressed if we DIDN'T have a secret site to interrogate terrorists.