Personally I don't think American culture is sterile; I think it is more of a problem of lack of unity of heritage. There are so many different lifestyles and customs that became combined so shortly ago in our country that we don't really have a common culture outside of the consumer culture (go to your local mall and play anthropologist someday). So I think, in many ways, that our "lack" of culture is the very thing that defines our culture. Does that make sense? I think that is often the defining trait of a "young" country (well, a young country built on the backs of an old one, but that's neither here nor there).