A recent comment on this website very correctly noted that guns provide options. I thought I would take a moment to expound on that point, since it seems to be lost on those opposed to gun rights:
Carrying a gun for self defense gives an individual options. If confronted by a violent criminal, that armed individual has the option of using the gun in self defense – but they are not compelled to use the gun. Instead, a citizen who is armed for self defense simply has the option of using the gun to defend themselves if they believe it to be prudent to do so.
An example of this fact can be seen in a Wilkes-Barre, PA robbery from a couple months ago: In that robbery, a disabled man was approached by two criminals who threatened him with a metal pipe and demanded his wallet. The victim was lawfully carrying a concealed handgun for self defense, but chose to just hand over his wallet rather than opening fire. However the criminals continued to advance on the man, even after he gave them his wallet. It was only then that the man fired his gun in self defense, wounding a criminal and saving his own life. In this case, the robbery victim could have opened fire on the criminals as soon as they threatened his life with the metal pipe, and would have been legally and morally justified in doing so. But he chose not to use his gun at that time, and instead complied with the robber’s demands. His gun gave him options, and the presence of his gun in no way compelled him to open fire. (Note: I’m not going to second guess his choice to not immediately defend himself, since no one is really qualified to second guess self defense actions of crime victims, and that is not the point of this article.)
Guns are like fire extinguishers, in that they can be used to end a life threatening situation. Just as having a fire extinguisher in the kitchen doesn’t compel a homeowner to use that fire extinguisher to put out the candles after dinner, having a gun doesn’t compel a gun owner to open fire the second thing seem slightly awry. Having a gun (and a fire extinguisher) is a wise and prudent choice, as it is better to have a life saving tool and (hopefully) not need it, then to need that life saving tool and not have it.