From Harvard Magazine: http://harvardmagazine.com/2004/09/death-by-the-barrel.html

"Statistically, the United States is not a particularly violent society. Although gun proponents like to compare this country with hot spots like Colombia, Mexico, and Estonia (making America appear a truly peaceable kingdom), a more relevant comparison is against other high-income, industrialized nations. The percentage of the U.S. population victimized in 2000 by crimes like assault, car theft, burglary, robbery, and sexual incidents is about average for 17 industrialized countries, and lower on many indices than Canada, Australia, or New Zealand.

"The only thing that jumps out is lethal violence," Hemenway says. Violence, pace H. Rap Brown, is not "as American as cherry pie," but American violence does tend to end in death. The reason, plain and simple, is guns. We own more guns per capita than any other high-income country—maybe even more than one gun for every man, woman, and child in the country. A 1994 survey numbered the U.S. gun supply at more than 200 million in a population then numbered at 262 million, and currently about 35 percent of American households have guns. (These figures count only civilian guns; Switzerland, for example, has plenty of military weapons per capita.)

[...]

In general, guns don’t induce people to commit crimes. "What guns do is make crimes lethal," says Hemenway. They also make suicide attempts lethal: about 60 percent of suicides in America involve guns. "If you try to kill yourself with drugs, there’s a 2 to 3 percent chance of dying," he explains. "With guns, the chance is 90 percent."

That's a lot of preventable deaths. Suicide has been repeatedly shown to be an impulsive act; prevent the completion of the impulse, and the individual rarely tries again. Putting up fencing at bridges, along with phone numbers for crisis hotlines, reduced the number of jumpers without a corresponding increase. When Israel restricted its soldiers from taking home their weapons on the weekends, it saw a decrease in weekend suicides, without a corresponding increase during weekdays. The key point: guns make crimes and suicides more lethal. 

One argument a lot of anti-control gun activists use is the figure of 1-2 million crimes prevented by responsible gun owners. There's one problem with that figure: it's a lie. [See http://www.hsph.harvard.edu/research/hicrc/firearms-research/gun-threats-and-self-defense-gun-use/index.html ], which is excerpted here: 

Guns are not used millions of times each year in self-defense

We use epidemiological theory to explain why the "false positive" problem for rare events can lead to large overestimates of the incidence of rare diseases or rare phenomena such as self-defense gun use. We then try to validate the claims of many millions of annual self-defense uses against available evidence. We find that the claim of many millions of annual self-defense gun uses by American citizens is invalid. 

Where did this come from? Apparently, Gary Kleck is the man behind the invalid numbers. David Hemenway and his coworkers have refuted his claims several times: http://www.hsph.harvard.edu/faculty/david-hemenway/files/Review_of_Gary_Kleck_2004.pdf (note: this is a pdf file.)

They have also found that more guns equals more deaths. http://www.hsph.harvard.edu/research/hicrc/firearms-research/guns-and-death/index.html

Indeed, as Adam Gopnik pointed out in his blog [http://www.newyorker.com/online/blogs/comment/2012/12/the-simple-truth-about-gun-control.html], in countries like Scotland (after Dunblane); Australia (after Port Arthur), and Canada (after Ecole Poly), strict gun control laws enacted after each incident resulted in a profound reduction in gun deaths. 

Isn't it time the US did the same?