
Well, possessing and carrying firearms certainly isn’t a human right since it’s not mentioned in any global human rights treaty or declaration. Neither is it a right that’s demanded by the majority of people in the world. It seems to be an exclusive preoccupation of many in the U.S., where the Second Amendment to the Constitution declares:
A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed. (source)
Guns and violence
Whether or not this is an example for other countries to follow, or whether or not this is a good thing for the U.S., are questions worth pondering. The fact that Americans kill one another at a much higher rate than do residents of comparable western European nations, and that this gap persists despite a roughly 40 percent drop in the US homicide rate in the last 15 years or so, is a first indication the answer to those questions is likely to be negative. Gun rights in the U.S. has led to widespread gun possession:
The United States has the largest number of guns in private hands of any country in the world with 60 million people owning a combined arsenal of over 200 million firearms. (source)
And it so happens that this widespread possession is correlated with high crime rates. However, this correlation between gun ownership and violence doesn’t have to be causal. Both numbers can have a third factor causing them both, such as high levels of endemic aggression. Reducing the number of guns would then perhaps fail to reduce the levels of violence. However, I don’t believe in such a third factor and there is proof of a causal link between guns and aggression:
Do guns make men more aggressive? Looks like the answer is “Yes, unless they handle guns a lot.” … We tested whether interacting with a gun increased testosterone levels and later aggressive behavior. Thirty male college students provided a saliva sample (for testosterone assay), interacted with either a gun or a children’s toy for 15 min, and then provided another saliva sample. Next, subjects added as much hot sauce as they wanted to a cup of water they believed another subject would have to drink. Males who interacted with the gun showed significantly greater increases in testosterone and added more hot sauce to the water than did those who interacted with the children’s toy. Moreover, increases in testosterone partially mediated the effects of interacting with the gun on this aggressive behavior. (source)

second amendment cartoon by John Cole
Deterrence
On the other side of the argument, you have people claiming that more guns mean less crime. Gun possession is supposed to have a deterrent effect on criminals. At first sight, that sounds convincing: when potential criminals know that there’s a high probability that their potential victims carry or possess guns, they may think twice before deciding to rob someone. Still, how does this square with the correlation mentioned above? Why is there so much crime in the U.S. if gun ownership deters crime? The only explanation is that crime rates would be even higher in the U.S. without gun rights:
Because … while we hear about the murders and accidents, we don’t often hear about the crimes stopped because would-be victims showed a gun and scared criminals away. Those thwarted crimes and lives saved usually aren’t reported to police (sometimes for fear the gun will be confiscated), and when they are reported, the media tend to ignore them. No bang, no news. It is quite clear that we have not seen any massive increase in crime, even though we have shifted from a situation where about 10 states allowed nearly every law-abiding adult to get a concealed carry license to a situation where 40 states do. So the fears of gun control proponents certainly have not materialized. (source)
The argument is that while guns may be dangerous and lead to murders and violence, gun ownership for self-defense purposes often prevents violent crime and thereby saves lives. Gun rights activists claim that on balance the gain is larger than the loss. Moreover, they argue that other rights can also cost lives (free speech for nazis can lead to authoritarian rule, rights ensuring that people have a fair trial can result in criminals escaping jail sentence etc.).
Supposing all this is true, the question is then what on earth is wrong with the American psyche that even a supposedly massive deterrent effect still produces crime rates that are higher than in other comparable countries that don’t have the same deterrent? I don’t think there’s anything particularly wrong with Americans, and hence this deterrent effect is probably largely imaginary (as are other deterrent effects).
I should also mention that the “more guns, less crime” narrative that claims that the number of lives saved by guns is larger than the number lost, often relies heavily on some seriously flawed research by the notorious John R. Lott (read more about this guy’s methods here and here). If you see or hear anyone defending gun rights and using Lott’s work, you can safely move on.

gun rights cartoon by Pat Bagley
Self-defense
However, even if it’s not clear that a consequentialist or utilitarian defense of gun rights can work (that in other words gun rights produce overall higher utility levels that gun prohibition or gun control), it’s still possible to make a rights-based case for gun rights. You can argue that people have a right to the means of self-defense, whatever the overall balance of violence. I personally think that this is the strongest of the arguments in favor of gun rights. If you can connect gun rights to existing human rights such as the right to life and the right to physical security, you can make a strong case.
For decades, liberals have insisted that the Constitution assumes—even if it does not explicitly spell out—a right to bodily autonomy. This right, long disputed by conservatives, is a basis for arguments in favor of abortion rights and gay rights. Liberals who support gun rights find a similar implied right to own weapons: after all, they say, what is the right to bear arms but the ability to protect your body from criminals as well as the government? The right to bear arms gives you a mechanism to protect your bodily autonomy from attack. (source)
This link to abortion is an interesting one. Both abortion and gun rights can be defended on the basis of bodily autonomy, self-determination and self-defense. But then again, it’s rarely the same people who defend abortion rights and gun rights. On the contrary, gun rights activists are often decidedly against abortion. There’s an interesting story here about a campaign against abortion in black families.
“BLACK CHILDREN ARE AN ENDANGERED SPECIES,” the billboards proclaim. Posted in dozens of locations in Atlanta’s black neighborhoods, they direct readers to a Web site that denounces abortion as a racist conspiracy. Through them, the pro-life movement is sending a message that it cares about the lives of black people. But does it?
The Web site plays every race card in the deck. It says “abortion is the tool [racists] use to stealthily target blacks for extermination.” It calls on readers to “expose the insidiousness of the pro-abortion agenda and its real target: the black community.” It touts the support of “Dr. King,” a niece of Martin Luther King Jr. “I know for sure that the black community is being targeted by abortionists for the purpose of ethnic cleansing,” she asserts.
What’s the basis for these charges? The campaign points to eugenic ideas and influences in the early birth-control movement. But its chief evidence is abortion rates. “Abortions in the black community occur at 3x the rate of those among the white population and 2x that of all other races combined,” the site points out. “The truth screams loud and clear—we are killing our very future.”
The numbers are provocative. But there’s something odd about the billboards. The child who appears beside the text is fully born. Abortion doesn’t kill such children. What kills them, all too often, is shooting. If you wanted to save living, breathing, fully born children from a tool of extermination that is literally targeting blacks, the first problem you would focus on is guns. They are killing the present, not just the future. But the sponsors of the “endangered species” ads don’t support gun control. They oppose it. … Maybe that’s why blacks, unlike whites, strongly favor gun control. (source)
This example of how gun control can help the black minority in the U.S. is often countered with another example of how it has been used to work against blacks. Gun control does indeed have a history as a tool for subjugation of blacks.
After the Civil War, the defeated Southern states aimed to preserve slavery in fact if not in law. The states enacted Black Codes which barred the black freedmen from exercising basic civil rights, including the right to bear arms. Mississippi’s provision was typical: No freedman “shall keep or carry fire-arms of any kind, or any ammunition.” (source)
Gun control left the freedman defenseless against the KKK and unable to form militias to resist white terrorism. However, I fail to see how a very specific and largely closed period in American history can justify rights more than 100 years later, especially if there are contemporary examples pointing the other way.

A final self-defense argument against gun control is the possible revolution against a dictatorial government. The “people” may need firearms to rise up when government becomes tyrannical. Now, I know that there’s currently a lot of right-wing anti-Obama hysteria and paranoia doing the rounds about a supposed dictatorial plot. However, I think it’s very unlikely that any U.S. government can ever achieve tyranny, even if it very much wanted to. And suppose it did, how can you be so foolish to believe that handguns would allow the people to defeat the superior firepower of the U.S. government?
Regardless of your position on the Second Amendment, whether the Second Amendment’s right to keep and bear arms is “fundamental” to “our scheme of ordered liberty” is severely questionable. Certainly other countries are able to have something that we would call “ordered liberty” without ironclad protection of firearms ownership rights. And while historically there may have been instances where the ability of the citizenry to safeguard or expand “ordered liberty” via ownership of firearms, the restrictions that are allowed on the Second Amendment under Heller ensure that the government’s advantage in firepower will be insurmountable in such hypothetical circumstances nowadays. (source)

gun control cartoon by Nate Beeler
Gun control
What I personally would favor is not prohibition but extensive gun control, including bans on gun possession by felons or minors etc., bans on the open or concealed carry of guns in certain places such as schools etc. I can understand why some people think they need a gun for self-defense. The question is, however, if restrictions on gun rights will still be possible after the recent Supreme Court case, McDonald v. City of Chicago.
The argument that gun control laws don’t work and don’t bring down the number of crimes isn’t necessarily correct. You would have to measure against the counterfactual, which is very difficult: without gun control laws, crime would perhaps have gone up, so a failure to reduce crime isn’t necessarily a failure of gun control laws. Maybe they simply reduced the growth in crime rates. Also, failure to bring down crime rates may be not the fault of gun control laws but of the way they are designed or enforced. And anyway, there is evidence that gun control laws do bring down crime rates.
Some data
Public support for gun rights in the U.S. is on the increase, at least among those parts of the population that don’t bear the brunt of gun violence, i.e. whites:


Whites said by a plurality of 50 percent to 44 percent that it was more important to protect the right to own guns than to control gun ownership. But an overwhelming majority of blacks, 72 percent to 20 percent, said it was more important to control gun ownership.
Here are a few maps that show the adoption of laws in the U.S. that allow people to carry concealed weapons. Concealed-carry laws have become much more permissive. There’s another map here with a state-by-state detail of the laws on open carry and concealed carry.
More on the second amendment here.
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