The Threat is Real, very real.

[Klem]

Until they find some evidence that points to a more interesting motive it's just some old crazy b*stard's planned suicide. We know from his neighbours that he was anti-social, and we also know he was socialised by a morally corrupt father; a convicted bank robber. For a while his dad was the FBI's Most Wanted so an important person in his sons eyes. His dad stood up to the rest of society while on the run. That sort of thing can leave an impression on a son.

Getting towards the end of his meaningless life and wanted to go out in familiar infamy. Engineers his own movie where he gets to star as the master antagonist; for a brief moment the focal point of an entire population, just like his dad. The apple didn't fall too far from the tree.

He sends his partner off to the Philippines to be with her family and then wires her $100K (her two sisters gave an interview last night). Prima facie she didn't know.

While it is exciting to think there might be a second shooter on the grassy knoll, or a covert Islamic sleeper cell the most likely reason is the one that best fits the evidence - relevance deprivation syndrome. He was a big stakes gambler who saw suicide as his last hand, with potentially the biggest payout of his miserable life. In his own twisted mind he probably won.