Guilty After Proven Innocent

The Obama administration is considering holding suspected terrorists even after they are found innocent. Mark Kleiman argues that the US should be allowed this right:

Some of [the Gitmo detainees] are there due to mistake, and ought to be released; the others were members of groups engaged in warfare against the United States, and should be held as long as the conflict lasts, even if that turns out to be forever.

I understand why some captives in wartime are dangerous even if no legal case can be made against them. But if these detainees are prisoners of war, they should surely be given full prisoner of war status. And their detention should be tied to how long the wars in Afghanistan and Iraq last, not to the Global War On Terror, which was designed to be never-ending.