Sorry but in addition i wouldlike to say that keeping him alive makes him a kind of martyr as well to our enemy. He is, after all, being unjustly incarcerated by the eveil satan that is the USA. Plus you have the types that will forever demand his release thru hostage taking or other threats.
That's a very good point and one I hadn't thought of.
Three words: Boo Freakin' Hoo.