I respectfully disagree. Of course, the guy became a traitor the moment he joined up with the Islamic enemy and set his sights on Americans. But, that doesn't mean he gave up his rights (after all, the Constitution specifically sets forth rights for those accused of treason). The point of Constitutional rights for people accused of crimes, even heinous crimes like this one, is not simply to protect the rights of the accused. It's also to protect everyone else, by limiting the power of the government, and expanding the power of the people.
Taken together, the 5th amendment right to due process and the 6th amendment right to trial by jury mean that the government does not have the power to deprive a citizen of life, liberty or property without due process of law, and that such due process must include the citizenry (as represented by the jury). Allowing the government to ignore all of that, name a citizen as an "enemy combatant" and deny him due process--even where, as here, he has committed a heinous act, even an act of war--represents a tremendous expansion of the power of the government, and a corresponding decrease in the power of the citizenry. Sure, it might yield the "right" result in this case, but once you allow the government to do that to one guy (even a scumbag like this), it makes it that much easier for them to do it to someone else (and don't think for a second that the 0bama admin wouldnt love to do it to a "radical" Christian preacher, or tea party "militant").
Nope. He forfeited any constitutional rights he may have had the moment he signed on as an Islamic militant combatant as a soldier of death (jihadist). He belongs in a military prison where they can extract all the information they can about his Islamic comrades and Islamic terror connections and ongoing terrorists plots, then a speedy military trial and a short drop from the hangman’s platform.
Let it be known that swift justice awaits treasonous Islamic terrorists.