is prejudicism apart of human nature and we just plain simple stupid?

The obvious answer is that we should not be afraid. However it is not as simple as that unfortunately. I am white. (As you can see from that little cooky picture to the left.) I have several black friends, and we do not see eye to eye all the time, but I am not afraid of them at all. They are some of the nicest friends I could hope to have. My ex-gf is from Kenya, and we are still very close friends. But there are plenty of black people that I do not trust at first sight. It is not that I'm prejudice, the problem is that I do not know which ones have jobs and are honest members of society, and which ones are angry, hateful thugs. And there are alot of the thugs out there. A HUGE percentage of black Americans are criminal minded, and many of the black people who are not criminally oriented, are difficult to tell apart from them because of music and culture and the atmosphere they were raised in. You are a product of your environment. The friends I mentioned, are African American, as opposed to Black American. African Americans, for the most part, are different. They are Africans, who have come to America recently. They dress different, they treat you openly from the start. And there are plenty of Black Americans who are the same, but so many of them are just plain scary. I wonder if they are a threat just because I am white and walking down "their street". So I stick to "my streets" and avoid that crowd as much as I can. And I think it is a shame, because I will never get to know those in their community who are great people. But getting stabbed by some thug while looking for those nice people isn't worth it. Am I racist??