Many were not captured on a battlefield, that's the problem.
Of the total number of prisoners being held at Gitmo, how many were not captured on a battlefield?
Also, comparing US actions today with german camps in WW2 is exactly the downward spiral in the perceptions of what should be considered right and justified vs. something plain wrong.
For the ones that were captured on a battlefield, they should be held w/o trial or charges being brought against them. To charge them with crimes, take them to trial and sentence them, would be exactly what the Soviets did to the Germans at the conclusion of WWII.
And the answer to your last paragraph is easy. It's their right as a human person. Only exceptions: See Vikings post.
If they are combatants, all they get is imprisonment until the conflict is over, it's all they are entitled to.
