Any individual (or group of individuals) who initiates physical force against others is a dictator — a monster — and should be treated as such. To use force in retaliation — in self-defense against those who initiate it — is not a moral option, but a moral requirement. A moral individual has nothing to gain from being assaulted, but has much to lose if one does not defend onself.
The use of force, in and of itself, is not evil — but to initiate (start) force is. Contrary to the doctrines of the pacifists, using force in self-defense is a good (force in self-defense may not always be possible, or effective, but this does not change its moral status as an act of self-defense).
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Under capitalism, it is the government’s job to use force to defend its citizen’s rights; however, the government is not omnipotent, and it is not omnipresent: it cannot be everywhere.
In cases where the police are not present to resolve a criminal situation in time to prevent an irreversible situation, one has the right to those means necessary to protect themselves, until the police can arrive to handle the situation, i.e., an intrusion by a would-be rapist when a woman is alone in her apartment.
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The right to own a firearm is an application of the right to self-defense, i.e., the right to obtain the means to defend oneself. The right to self-defense is itself is a corollary of the right to life (a corollary is an implication of a principle).
It would be absurd to say one has the right to life in theory but does not have the right to the means necessary to protect that life. It would be like saying one has the right to life, but not the right to purchase food. This is what opponents to the right to own a gun for self-defense are really against the right to life.
Unfortunately, it is the right to life, that is ignored in the debate over the right to bear arms, both by its opponents and by its so-called defenders! As Adam Mossoff writes in Capitalism Magazine:
“The field of battle on which gun control should be fought is exactly on this issue: man’s rights. Statistical arguments on gun control are a red herring — as the leftists’ appeals to hungry children or the environmentalists’ appeals to clean parks are also meant to distract their opponents from the fundamental issues at stake. While the National Rifle Association (NRA) and other defenders of the right to bear arms argue over statistics and interpreting the Constitution, the real issues remain untouched and are sacrificed to the enemies of our freedom.”