The President's Speech: What About GTMO Detainees Who Cannot be Tried, but also Cannot be Released?

In his speech today, President Obama explicitly raised this perennial, maddeningly difficult issue.  But he stopped well short of proposing a solution. Instead he said that “once we commit to a process of closing GTMO, I am confident that this legacy problem can be resolved, consistent with our commitment to the rule of law.” That might well prove true---I sincerely hope it does prove true---but the question remains: exactly what does the United States plan to do with law of war detainees who it cannot try but who it also cannot release, having in mind the conflict's eventual end?  Elsewhere in his address, the President called on Congress to lift GTMO transfer restrictions.  Given that, perhaps the idea is detention within the United States, under some different legal framework?   It's unclear.