* Guns are not used millions of times each year in self-defense.
* Most purported self-defense gun uses are gun uses in escalating arguments, and are both socially undesirable and illegal.
* Firearms are used far more often to intimidate than in self-defense.
* Guns in the home are used more often to intimidate intimates than to thwart crime.
* Adolescents are far more likely to be threatened with a gun than to use one in self-defense.
* Criminals who are shot are typically the victims of crime.
* Few criminals are shot by decent law-abiding citizens.
* Self-defense gun use is rare and not more effective at preventing injury than other protective actions.
From here (with further explanation and peer reviewed research sources).