You're ignoring the payoff on invested resources. To "recruit" one of these schizophrenic ne'er do wells (or as the FBI called him, "a retarded fool"), the FBI has > a dozen agents working on it, cultivated CIs, a nigh-omnipresent surveillance operation, and effectively unlimited funds, over the course of several months. A corresponding effort by a group already under surveillance would noticed incredibly quickly and absorb massive amounts of resources that could just as well be used directly for ill.

I agree. Every one of those agents should be prosecuted under the Patriot Act.