I've seen plenty of human beings shut right down with it.
Discussion
To each their own, I kill a lot of pigs, in different ways, different sizes, different shot placement, and I can tell you, 9mm is not enough to stop a 300 pound man with a knife at ten feet unless you hit center face, spinal cord, or one of five major arteries which would take amazing skill under duress that probably one in ten trained soldiers with combat experience could pull off. Good luck!
Looking at the statistics of handgun survivability, there is a marked difference between any handgun and any rifle (firing an intermediate or above cartridge). I think 9mm is a decent enough compromise at least if you have enough rounds on you. To counterpoint what Jack is saying about a revolver being enough, that is not the case anymore. Attackers are grouping up exponentially more often. 6 rounds on tap is NOT enough. But also one 17 round magazine (welcome winter carry!) is also not enough in case you have a malfunction. You should be training to dump the mag, slap in a new mag, and rack the slide, so you ALWAYS need at least one spare mag, no matter the capacity.
Once again, I can’t disagree, but if a semi automatic with spare mags is an urban necessity, why not 10mm or at least .357 Sig? When it comes to adequate penetration, proper expansion, and bone mass is concerned, 9mm doesn’t cut it. A decent layer of visceral fat stops a hollow point 9mm as effectively as body armor. Obesity rates in America again? Fifty percent at least? You wouldn’t hunt a 200 pound puma with your 9mm, are humans not dangerous game in these circumstances?
Because it's much, much easier to carry a compact 9mm. 357 Sig is effective but really, really loud. There are no excellent compact 10mm pistols that I've seen. (I don't consider Glocks to be excellent, and I would not want to shoot the shorty 10mm, anyway.)
All handguns are a compromise. A modern thin 9mm with enough capacity and good defense ammo stop be more than enough RI not be outgunned in most cases.