Terrorists are not criminals. They are illegal enemy combatants, operating beyond the sanction of both US law and the Geneva Conventions, and their detention needs to be reflective of this.
Should we put them in :"Gen Pop"?
Matthew 10:34Think not that I am come to send peace on earth: I came not to send peace, but a sword.
Criminals are people who break the law. In administering justice, the criminal is both subject to the law (and the law's sanction) and protected by the law.
The terrorist does not merely break the law. The terrorist dismisses the law. The terrorist of his own volition places himself outside the law, claims not to be subject to the law, and therefore has no claim on the protections of the law.
There is no justice in giving terrorists the protection of law. They sneer at it, they have contempt for it, so let them do without it.