Not only Americans, but there are still many other people who do not know Bitcoin. Even many entrepreneurs know Bitcoin, but they don't want to use Bitcoin as a media transfer. Many people think Bitcoin is a very confusing thing, let alone Bitcoin prices are easy to change. So they are too risky to accept Bitcoin as a media transfer. In my country, there are also many people who do not know Bitcoin. That makes them not knowing about Bitcoin because there is not much news about Bitcoin information, probably in America like that.