He's an advocate for .45 ACP, but carries a 9mm only because of arthritis.
He's said in the past that a .45 ACP might be only 10% more effective than a 9mm, but that's a lot when someone is trying to kill you. I'd say that's dang reasonable.
Forgive me my nonsense, as I also forgive the nonsense of those that think they talk sense. Robert Frost