I am the NRA

Oh yeah:

It also appears that Patock, who told police he was fresh off a visit to the NRA, has a long-standing grudge against a politician (surprise!) -- specifically, former President George W. Bush.

[Patock's former neighbor, Jim] McFarland said Patock owned several guns and displayed aggressive behavior. When asked to describe Patock's character, McFarland responded, "Weird. He hated the president (George W Bush). He hated everything. He said if he got a chance he would shoot the president."
McFarland said he wasn't surprised that Patock turned up in Washington.