The only real due process requirement (which admittedly require scrupulous care in order to forestall obvious possibilities for abuse) is a fair evaluation of evidence concerning whether or not 1)a given organization is, in fact, a terrorist group, and 2)whether or not a given prisoner is, in fact, an agent of said organization. If the answer to both questions is "yes", then the prisoner is the enemy general of mankind, to be dealt with as wolves are.
Sent to Yellowstone Park and allowed to prey on ranchers' livestock? ;-)