In Crash, director Paul Haggis clearly illustrates the reality and effect of inter-racial collisions that exist and happen in our society. Officer Hansen thought Peter was reaching his pocket for some kind of weapon and in seconds he made his decision and fire at Peter.
The elderly man turns out to be Laius, Oedipus' father.
Some people may not be as receptive to change as others, but there are events that can change people. While some assumptions may be minor, like if a certain candy bar is satisfying; other assumptions could detrimentally impact many lives and bring long-lasting consequences.
The film shows a few scenes that define racism and power.
Similarly, like Will Smith who fought for himself and his son so that they too could be better off after struggling through very tough times This works against the liberal argument that exposure eventually promotes tolerance. He is very quiet and the peaceful person in the whole movie and due to nature of his work, he usually works late at night.
Thus, analogizing the racism of the Iranian and the white policeman is inaccurate because one has more cultural power, despite Ryan's perceptions of powerlessness.
I think Crash represents the race relations in America and shows that how misconceptions and lack of communication makes our life situations very unstable.