COULDNT THEY AT LEAST HAVE PUT HIM ON A NO-GUN LIST? "FBI Faces Tough Questions Over Orlando Shooting by Omar Mateen"

Why does it have to be All or Nothing in terms of Investigation into terrorism? Why not have a series of steps where you say possible probable definite According to which level a person might be on, that determines whether they can buy a gun or they can fly etcetera . the ultimate , being, of course arrested and incarcerated for being a definite threat.

http://www.newser.com/story/226689/fbi-faces-tough-questions-over-orlando.html

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