Ismael, I can understand why you're puzzled as to why Americans love their boomsticks.
In my case, I grew up in a rural area and my dad took me deer and duck hunting every year. He bought me a .22 rifle at the age of 11 or 12 and taught me how to shoot a gun right around that time. Not to get me into the "gun culture" mind you, but to teach me how to properly handle, use, and disarm a loaded weapon. He considered it safer for me to know how to fire and handle a weapon in case I ever came across one that may be loaded than to panic and possibly do something stupid. I will do the same for my children when the time comes.
Since I moved out for college several years ago, I've been out on my own and purchased a .38 pistol for firing range use and home protection. It's still sitting under my mattress and only gets pulled out to clean every now and again.
To many Americans, guns simply aren't a big deal. We grew up with them, used them as children, and it's not considered odd at all to own one. To you Europeans, it seems weird but when you grow up around stuff and use it responsibly (which 99% of the population does), it just becomes another thing people own and occasionally use.
Or check out my new webcomic: http://selfcentent.com/
