I don't understand this fear that some US politically-affiliated persons have of providing suspects of criminal activity with their guaranteed rights. If we are that convinced they are guilty, there should be ample evidence to convict without illegally-obtained or coerced statements.
Now, if they want to pass a law stating that those who are convicted of a criminal offense related to certain terrorism offenses may be subjected to coercive interrogation in order to gather further information related to intelligence, I really don't have a problem with that, particularly in cases where the death penalty can and likely will be sought.
But seriously. Read the ****er his rights, give him a lawyer, and convict his ass properly. Once we've established - fairly - that he's guilty of everything he's alleged of doing, then put him through the wringer for every scrap of information he has, but not one second sooner.