Hinkley's motive wasn't coherently political, but he didn't pick Reagan at random, and he didn't pick him because he thought Ms. Foster would be impressed by the murder of a retired actor.
If we found out that Reagan ran for President in order to try to impress his Mom and just went with whatever political agenda he thought would work, would that make his legacy not political? Let's not even get into W and daddy issues.
My first real tech job, the founder started the company in order to impress a stripper named Pam. Does that mean that starting the company was not an economic act? Pam was non impressed, by the way, and died of a heroin overdose. She was replaced by another stripper also named Pam, who also was not impressed.