In what way did the 9mm fail? The bad guy was wearing body armor. Shots to the extremities be it from 9 or .45 aren't likely to have any different effect on the terrorist. Stopping shots to the melon would have identical results from either cartridge. A rifle would be the first choice in that situation but the officer didn't have the time to retrieve a long gun.
Where did I say it failed or for that matter compare it to the 45? At least with the 9 he had a LOT of shots..and he shouda kept shooting.
I am not a 9mm fan my self
That said
The officer doing the shooting knocked the perp down and was able to keep him on the ground with the gun that he had.
So something was working even with the body armor
Perp Rehabilitated and we never attack anyone again.
Ya gotta pat the Officer on the back for keeping his head after the war with this guy started.
