As libertarians, we believe that people have rights. Each person owns himself and his legitimately acquired property. And if people have these rights, they have the right to defend them. If you have a "right" to free speech, for example, but don't have the right to stop someone who is using force to prevent you from speaking, your "right" doesn't amount to much.

As the great Murray Rothbard has said, "If, as libertarians believe, every individual has the right to own his person and property, it then follows that he has the right to employ violence to defend himself against the violence of criminal aggressors. But for some odd reason, liberals have systematically tried to deprive innocent persons of the means for defending themselves against aggression. It should be clear that no physical object is in itself aggressive; any object, whether it be a gun, a knife, or a stick, can be used for aggression, for defense, or for numerous other purposes unconnected with crime. It makes no more sense to outlaw or restrict the purchase and ownership of guns than it does to outlaw the possession of knives, clubs, hatpins, or stones. And how are all of these objects to be outlawed, and if outlawed, how is the prohibition to be enforced? Instead of pursuing innocent people carrying or possessing various objects, then, the law should be concerned with combatting and apprehending real criminals."

Some people argue that owning a gun isn't necessary to stop crime. That is the job of the police. In fact, though, states that do not impose many restrictions on individual ownership of guns have lower crime rates than those that do. As John R. Lott, Jr., the foremost authority on the statistics of gun ownership and crime, has said, "There is a clear consensus among economists about self-defense, gun-free zones, firearms and suicide, and concealed handgun laws. Among North American economists: •  Eighty-eight percent say that guns are more frequently 'used in self-defense than they are used in the commission of crime.' •  Ninety-one percent believe that gun-free zones are 'more likely to attract criminals than they are to deter them.' • Seventy-two percent do not agree that 'a gun in the home causes an increase in the risk of suicide.' • Ninety-one percent say that 'concealed handgun permit holders are much more law-abiding than the typical American.'• Eighty-one percent say that permitted concealed handguns lower the murder rate."

Some people acknowledge that people have the right to own guns, but they favor restrictions like gun registration. Lott's research shows that these measures aren't needed: "Whether in Canada, Hawaii, Chicago, or Washington, D.C., police are unable to point to a single instance of gun registration aiding the investigation of a violent crime. In a 2013 deposition, D.C. Police Chief Cathy Lanier said that the department could not 'recall any specific instance where registration records were used to determine who committed a crime.' The idea behind a registry is that guns left at a crime scene can be used to trace back to the criminals. Unfortunately, guns are very rarely left at the scene of the crime. Those that are left behind are virtually never registered—criminals are not stupid enough to leave behind guns registered to them. In the few cases where registered guns were left at the scene, the criminal had usually been killed or seriously injured. Canada keeps some of the most thorough data on gun registration.