From what we have learned about the guy, I draw 2 conclusions so far:

 

1) Systemic failure.   Lots of red flags.   I agree with all that. 

 

2) His motivations are a whole soup of things.   Anger management issues.   Religion.   And, the fact that he was gay and had a hard time reconciling his gayness with his religious views.   Throw in his anger management problems, and you have an explosive mix.  

 

Why I think he was gay. 

 

This guy had some deep inner conflicts, anger management issues, and he just flipped out.   He was on some kind of FBI watch list but the fact that the FBI dropped him from the list is what allowed him to buy those guns without setting off some kind of alarm in the system.  We need to tighten that up perhaps. 

 

But what this has to do with immigration is almost nothing, because he was not an immigrant.

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