It is true that as early as 2002, the Bush people allowed as how, since Afghanistan was a signatory to the Geneva Convention on treatment of captives, and the Taliban had been the government, they would have to treat Taliban fighters as prisoners of war. But concurrently, they also said
At root, they said they could do what they wanted with individuals scooped up in their "war on terror" and the hell with legality.
Vast amounts of litigation, much Congressional posturing and some legislation, and years of prisoner abuse in various U.S. lockups around the world have followed. Guantanamo is only the most public site of all this. Many of us who supported President Obama's election expected the constitutional law prof to clean up after Bush's brazen disregard for the painfully erected system of international law. He did a lot less than we expected. Apparently when you are the most powerful Commander in Chief in the world, legal limits look like minor obstacles to be evaded, much of the time.
So it's good to see the Bergdahl release treated as simply a prisoner of war swap. Republicans don't like any of this. They don't like releasing anyone from Gitmo, they don't like Bergdahl's dad's beard, they don't like the President getting things done. They don't like treating Afghan adversaries as human. They want full spectrum world dominance as the core their "American exceptionalism." For the empire, law is an illegitimate infringement on the freedom of the guys with the best guns.