It's amazing how Boing Boing goes out of its way to show that terrorism is impossible and thus our guarding against terrorist acts must be the height of both stupidity and oppression. While I wrote just previously about the wrongness of a bunker mentality, I do believe (naturally) in using investigative efforts to locate those who might be inclined to commit acts of terror.
The fact that the particular folks mentioned in the linked story were fools (and, I don't necessarily take one "security guru"'s word on that) doesn't mean that they weren't ripe for the picking by someone with better knowledge on how to commit mass murder. Finding them and incarcerating them, thus removing them from the field of play, seems like a good enough objective on its own.
And as usual, Boing Boing attacks, but it provides no real alternatives.