It's simple really. It cost the GOP no bad Karma to let Cheney and Bush open the thing. The President called it a "military camp" so legally it was the same as keeping these bad guys in a tent in Iraq.

For Obama to MOVE THEM would have required some kind of law to put them in Federal courts, or even standard Military courts. Also, congress threatened to EXPLICITLY tell the President no funds were available.

... Kind of like how the 1980 congress told Reagan there would be no funds available to trade for hostages. In 1980 Reagan just went ahead and BROKE THE LAW something Obama has too much respect to do. The issue was divisive enough That Obama couldn't count in his own slim majority to vote on his side. Because Obama doesn't RULE the Democrats like Cheney did.