One could look at the whole thing as a matter of statistics and it could likely explain why some people are quite comfortable carrying something like .22, .25, or .32. I myself virtually always carry a .32 auto.
Assuming our present rate of violent crime in the US, (yes I realize this can vary drastically from city to city and so on and also that crime has actually been on a downward trend), the odds of the average American becoming a victim of violent crime is around 0.4% in a given year. Of course we realize that very unlikely most certainly does not equal impossible, so we carry a gun. That brings us to the next statistic.
According to that gunfacts.info site, in >99.1% of instances in which a gun is used for self-defense, the gun does not need to be fired to prevent the attacker from committing their crime. In which case, it doesn't matter whether you're armed with a .25, or a 12 gauge, or anything in between, merely showing the would-be attacker that you have a gun is enough to stop the attack the vast majority of the time.
Let's do some math, if the odds of you getting into a situation in which you need a firearm in a given year is 0.4%, and the the odds of you actually needing to fire your gun in such a situation is <0.9%, we come to the conclusion that your odds of having to actually fire your gun in self defense are 0.0036%.
But wait, there's more! There are basically two ways in which getting shot can stop an attacker, either getting shot does sufficient damage to the attackers body in such a way as to incapacitate them or they stop on account of the psychological realization of, "Oh my God, I've just been shot, and if I don't get help soon I will likely die!" Unfortunately, reliable statistics don't exist on how effective .25acp (or any cartridge for that matter) is in these regards. But we have to agree that at least some of the time .25acp will indeed be effective for one reason or another, that is we can agree the odds of it being effective are not 0%. That would cut the chances that a .25acp proves inadequate even further below 0.0036%. For instance, if we were to estimate for one reason or the other (not taking into account variables like shot placement, number of hits, etc), that a .25 proved effective only half of the time, the odds one you needing something bigger than a .25 auto would be 0.0018%.
Yes, there are a ton of other variables, and that in the real world, the numbers aren't quite so neat, but point is, in making the long story short:
It is quite unlikely anyone will need to use a gun for self-defense in the first place, it is more unlikely still one would ever need to fire their gun in self-defense, when multiplied by the fact that a small caliber isn't necessarily ineffective, it is even more unlikely still that a small caliber handgun will prove inadequate.
As I've said, extremely unlikely however does not mean impossible and anyone who feels they need and/or want theoretically better odds can carry accordingly should do so, I am not knocking people who prefer larger calibers whatsoever, I think it's wonderful that we have that choice, I just find it odd that some make it sound like people who carry smaller caliber weapons are constantly putting their own lives in grave danger by doing so.
sources:
the FBI crime statistics
http://www.fbi.gov/about-us/cjis/ucr/crime-in-the-u.s/2010/crime-in-the-u.s.-2010/tables/10tbl01.xls
Gunfacts.info
http://gunfacts.info/pdfs/gun-facts/6.0/Gun-Facts-v6.0-screen.pdf (pg. 11)
Assuming our present rate of violent crime in the US, (yes I realize this can vary drastically from city to city and so on and also that crime has actually been on a downward trend), the odds of the average American becoming a victim of violent crime is around 0.4% in a given year. Of course we realize that very unlikely most certainly does not equal impossible, so we carry a gun. That brings us to the next statistic.
According to that gunfacts.info site, in >99.1% of instances in which a gun is used for self-defense, the gun does not need to be fired to prevent the attacker from committing their crime. In which case, it doesn't matter whether you're armed with a .25, or a 12 gauge, or anything in between, merely showing the would-be attacker that you have a gun is enough to stop the attack the vast majority of the time.
Let's do some math, if the odds of you getting into a situation in which you need a firearm in a given year is 0.4%, and the the odds of you actually needing to fire your gun in such a situation is <0.9%, we come to the conclusion that your odds of having to actually fire your gun in self defense are 0.0036%.
But wait, there's more! There are basically two ways in which getting shot can stop an attacker, either getting shot does sufficient damage to the attackers body in such a way as to incapacitate them or they stop on account of the psychological realization of, "Oh my God, I've just been shot, and if I don't get help soon I will likely die!" Unfortunately, reliable statistics don't exist on how effective .25acp (or any cartridge for that matter) is in these regards. But we have to agree that at least some of the time .25acp will indeed be effective for one reason or another, that is we can agree the odds of it being effective are not 0%. That would cut the chances that a .25acp proves inadequate even further below 0.0036%. For instance, if we were to estimate for one reason or the other (not taking into account variables like shot placement, number of hits, etc), that a .25 proved effective only half of the time, the odds one you needing something bigger than a .25 auto would be 0.0018%.
Yes, there are a ton of other variables, and that in the real world, the numbers aren't quite so neat, but point is, in making the long story short:
It is quite unlikely anyone will need to use a gun for self-defense in the first place, it is more unlikely still one would ever need to fire their gun in self-defense, when multiplied by the fact that a small caliber isn't necessarily ineffective, it is even more unlikely still that a small caliber handgun will prove inadequate.
As I've said, extremely unlikely however does not mean impossible and anyone who feels they need and/or want theoretically better odds can carry accordingly should do so, I am not knocking people who prefer larger calibers whatsoever, I think it's wonderful that we have that choice, I just find it odd that some make it sound like people who carry smaller caliber weapons are constantly putting their own lives in grave danger by doing so.
sources:
the FBI crime statistics
http://www.fbi.gov/about-us/cjis/ucr/crime-in-the-u.s/2010/crime-in-the-u.s.-2010/tables/10tbl01.xls
Gunfacts.info
http://gunfacts.info/pdfs/gun-facts/6.0/Gun-Facts-v6.0-screen.pdf (pg. 11)
