Golf ball to the head isn't reliable enough. I've seen it happen. Was at my second spazz school, and this girl called joanne, petite, kinda tiny, not the sort you'd expect a lethal long-range shot like she did, but she did it alright, got one of the care staff from a few hundred meters, right in the back of the head. Dropped the guy instantly, knocked him senseless alright, but he did get up again, without any longterm crippling injury.
Certainly funny as shit to watch though, tiny girl belting the golf ball with her driver and one-shot takedown of the staff member, a real elite sniper-style shot, that had us all, even some of the care staff who were closer at the time were laughing our arses off. I still remember the way he dropped like he'd been shot in the head with a rifle or pistol hollowpoint round, but he did survive the experience.
Not that I am for a moment suggesting people don't take golf pot shots at trump if they get the chance.