How to Waste Money and Lives

The U.S. Prison system doesn't seem to function the way it should. Incarceration rates and amounts in the U.S. are higher than anywhere else in the world. We also have one of the highest rates of death by firearms, behind only South Africa, Colombia, Thailand and Guatemala. In 2004, 29,569 Americans were killed due to gunfire. 16,750 of them (56%) were suicides and 11,624 of them (40%) were homicides. Only 311 were due to "legal intervention", meaning police firings. statistically, 1 out of every 100 people you see are carrying a concealed weapon. So, my question is now, "Why is America such an apparently dangerous country?"
I would disagree with those that say it's our media, specifically violent video games, movies, television shows, music and other forms. It's true, in a way, that our media is constantly pushing violence to its highest extreme, but don't other countries watch and listen to the same things as us? Don't they also have violent histories, corrupt politicians, complex economies and repressed minorities just like us? Then why is it that these other countries have such smaller amounts of death by firearms, such as Japan with less than 60 a year, or Canada with less than 800 a year, or Great Britain with less than 50 a year? These numbers just don't add up, not when you consider their rate versus population: Japan - 0.07, Canada - 4.78, England - 0.38, United States - 15.22! Canada is the second most harmful country I've referenced, but you're still over three times more likely to get killed by firearms in the U.S.
My question remains the same. I don't see any distinguishing characteristic between the United States and the other countries I'm using here that would account for such a drastic difference. And if we really are the most violent, what does that say about our country? History doesn't seem to play any role at all, seeing as how Canada is generally the most peaceful nation in this comparison, but anyone who tries to argue that Japan or England have peaceful histories is bound to fail; just take a look at World War 2 for either or the occupation of India by the English and you'll see your mistake.
I'm trying to find answers to this question on my own, but I don't seem to be having any luck. I'm just running into more devastating statistics, so I'll end this on my main question:

What makes America such a dangerous country?