It's human nature, sadly, (i.e., us vs them) and it's all over the world. My two cents: I think the best we can do is be aware of our biases and try to change our thought patterns.
I used to love working in different countries. I loved being the minority; I think I thrived on the attention. I was a principal in an international school and a parent (native to the country) sent me an email asking for her child to be removed from the black woman's class and put into the blonde, blue-eyed teacher's class. I was gob smacked. I refused her and offered her money back if she wanted. It turned out she wanted bragging rights to her duaghter being in the "ideal" teacher's class' the child rightly loved her teacher. This was introduction to the accepted prejudice in this culture. It was eye-opening, to say the very least!
Look at the world though - wars are started because of perceived external differences between groups. It's easier to say that you aren't as good as I am because you don't have the same features as I do. It's so much harder to learn about others, put differences aside and build bridges.
