Rap is a part of American culture, more so, it's the voice of the ethnic American culture. They feel generally stepped on, and rap is (or was) a way of expressing themselves. Ironically, the people that they feel (I'm not saying if they actually do or not) oppress them picked up on it, commercialized it, and now sell it all bottled up and nicely packaged. That's why all you get nowadays is the "thug" rap, about the *****es and hoes and whatnot - because that's what sells, so that's what the record companies pick up, and in order to get picked up and make money, that's what people rap about. It's really another case of capitalism ruining art.
Note: I don't like rap (can't really stand listening to 99% of it), but I do appreciate it's original intentions.
As to the video, I only briefly looked at it, but it looks like one of those overreacting pieces of trash that raves about how awful something is without truly understanding why it's bad. It also smacks slightly of of a religious background/objective.
