As to motivations for murder [View all]
Trying to apply reason to a senseless act is silliness. No one wondered what John Hinckleys or Arthur Bremers or Squeaky Fromme's political motivations were because they were severely mentally disturbed. Sirhan Sirhan and Garfield assassin Charles Guiteau even though he wanted a job as NY port commissioner were cuckoo. Or those who shot at FDR and TR. or Mark David Chapman. The list goes on.
The only POTUS assassination attempt that might be called truly political was Lincolns and John Wilkes Booths deck of cards was missing two aces, a king and had a couple extra jokers. Maybe JFK, but that's a stretch because Oswald tried to kill Edwin Walker prior to killing JFK. Maybe McKinleys assassin or the Puerto Rican guys who shot on the Blair House when Truman was there. But even then it was more likely the craziness latching onto politics as rationale for senseless acts.
Robinson is more likely to end up being of the same mold as Bremen or Fromme. Or even Hinckley. Check his streaming history to see how many time he watched White Lotus and when/how long he paused the DVR to pleasure himself to Sydney Sweeney.
Same for the crazy-ass jackasses that shoot up schools. The sole fact someone would plan and carry out an act like this throws standard rationale out the window.
But none of that changes the fact we're a nation awash in firearms.