I felt ashamed watching District 9. In the same vein as when I watch or read about the holocaust/slavery. That movie was a prime example of NOT learning from our past mistakes. I'm glad you brought up that film as I had kind of forgotten about it.
As we have been in the past... We were, as a people, united by our loathing and fear of anything different.
Which oddly enough is kind of on topic. Which is a sad thing.