Good Morning,
Firstly, I beleive this fellow has been in the military, not because of his marksmanship skills, but because of his choice of arm and appreication of the ground. He stakes out an area, looks for an egress route first, then a firing location, and establishes a kill zone. Whomever ends up in this kill zone makes no difference, the thrill for him is the act itself, and the empowerment he feels from it.
He is not going after any person or persons that are politically relevant, so i don't think he is Al Quieda/ Taliban. I think when he has an option, he shoots females, which indicates some frustration in that area. I also do not think if he were AQ/ TB he would taunt the police.
Terrorism is by nature geared towards third party fear, and while he is reaping the beneift from this, it is more of a byproduct than the main objective. I'm thinking that this activity is a product of his own feelings of inadequacy, and would have happened regardless of the current state of alert we currently employ. As such, if he was a soldier, he was not a very good soldier, wierd, standoffish, barracks rat, ect. Acceptance by peers in a military unit is extremely important. This being my thinkinig, I would bet that he is working by himself.
I'd be surprised if this is a AK variant, I'm thinking AR series with a scope or red dot. I know of very few 5.56 MM weapons that Can shoot with an AR, and the nature of the round when used on humans is a wounding, rather than killing round. I have had some expirence with AKs, and Even with a perfect arrangement, I don't think his kill to wound ratio would be as noteworthy. If he is a AK variant shooter, he is allot more lucky than .....well, i hate to say "good".
My thoughts on the subject. As a veteran of the beltway, I can only imagine what they are up against. I purpose we put a collective call into the Big Jumpmaster in the sky, for this guys arrest / detainment / demise prior to anyone else getting hurt.
God Bless,
Steve