3-4 women a day are murdered by their partners in the US. The legality or illegality of it beside the point. There are large segments of American culture in which it's accepted:
http://www.youtube.com/watch?v=Lm2l0pxYw-4
The point here is that human nature itself can sometimes be a nasty, brutal and vicious actor. The failings of human nature can't be blamed on one religion or one culture. If one concentrates on the negative in life, you'll find it. I've found that better results are achieved by concentrating on the positive aspects of our nature while keeping an eye and a leash on the wild beast we all have inside of us.