Everyone is racist/sexist/nationalistic, etc.
rac·ism (rszm)
n.
1. The belief that race accounts for differences in human character or ability and that a particular race is superior to others.
2. Discrimination or prejudice based on race.
Everyone is racist. No exceptions.
What makes you a 'bad' person is really dependent on what you actually do.
Everyone treats guys/girls differently. Everyone treats ugly/beautiful people differently. You see another member of your race (common example: I know a lot of koreans and chinese who get free food if they visit a place without many asians) and you treat them better. Or treat another race worse. List goes on.
It is impossible to not have any type of prejudice or pre-formed opinion at ALL. The question is really whether you allow your opinion to change, be introduced to new information, etc.
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I have friends from pretty much every race on Earth. Iranian grad student, Chinese, German, Taiwan, Korean, Dutch, France, India, Brazil, Peru, and more I can't remember off the top of my head. I have been called racist before for various silly/amusing things like commenting on how virtually all the koreans I know drink "barley tea". It is an ASSUMPTION I made based on someone's race. So yes, it can be considered racist. Is there any harm in it? The koreans I said this to thought it was funny/true, a different friend thought I shouldn't have said that at all. Either way, what matters most to me in my own personal interpretation is MY intent.
If my intent is to make conversation, get to know you better, etc. then I couldn't careless about perceived racism. If my intent is to belittle, ignore or excuse myself from treating you like a human being, then yea, call me on it.
Corvuus