"Do the Right Thing" was a very controversial film. At the time of its release in 1989, there were some people who didn't like it, who were bothered or confused by it, but I think they were either missing the point, or didn't realize that they were supposed to be bothered and confused by it. I think Spike Lee was trying to comment on the issue of race relations as he saw it, a very bothersome and confusing issue. He wrote and directed and acted in scenes that exposed racism from all sides. I saw racism coming from whites, blacks, Asians, and Latinos. The film portrays the issue as being one big mess and I think he's right.
Of course with every movie there needs to be some dramatic license in order to drive the point home. People who are upset about that are completely missing the point. Roger Ebert, Pulitzer Prize winning film critic, said, "Anyone who walks into this film expecting answers is a dreamer or a fool. But anyone who leaves the movie with more intolerance than they walked in with wasn't paying attention" (rogerebert.com). I think what Spike Lee wants us to do is identify with one or all of the characters. The film is a window into what is wrong with race and class situations as Spike Lee sees them. I think we, as an audience, need to accept that and get as much out of this film as we can.
The film also comments on the issue of class separation in the US. There is a scene where a rich Cadillac-driving man tries to drive down a street that some kids are playing in. They have loosened the bolt on a fire hydrant and they are trying to cool off from the hot day. The man at the kids from his car that he will be mad if any water hits his car. It is clear that he does not have any respect for people he considers to be "lower class". The kids respond to this mistreatment by spraying water all over his car and the man is soaked. This scene tips the blame in the direction of the rich man, and in a situation like that it would be his fault.
Taken in context, this film was made in 1989 and was probably written earlier than that, but I think the film is still relevant even today. America has made great progress since the beginning of the civil rights movement, but I think there is still progress to make, especially in the way that the middle and upper classes treat the lower class.