I oppose this, and always have.
I really should have refrained from commenting, because I don't have an answer. All I know is that, when people talk about say "when we migrated out of Africa", or "when we, the vikings populated Iceland", or "when we arrived on the Mayflower", then something doesn't quite connect. A sentiment something like your own maybe.
The public was also not well informed of what was going on. Officials just said there are some bad people, that they're related to 9/11, and we locked them up.
Many people bought this, and i think part of the problem is that the general public doesn't really believe in due process, innocent until proven guilty, or the rights of the accused, even the rights of the convicted. I see lots of echoes of this in all the "tough on crime" rhetoric that is popular now. People just want to label people as "bad" and make them go away forever.
You also have to think the people employed at these prisons enjoy torturing (why else would they do it for 20 years - how do they find these people in the first place?) so maybe they keep them around just to have people to torture.
As far as I can see there's no additional information in the Canary article