What is the main theme in R. Wright's Native Son?

The main theme of Wright's Native Son
has to do with the context of fear that people are forced to live under when
institutionalized racism is present in society.  The novel's protagonist Bigger Thomas
is so afraid that he will be accused of rape that he unintentionally murders Mary
Dalton.  Again, his fear causes him to act irrationally, irresponsibly, and immorally to
cover up his crime.  Bigger then becomes consumed by the fear of being caught that he
continues to behave in strange ways.  When he exerts violence against his girlfriend
Bessie and is caught, this rape and murder go virtually unnoticed when paralled to the
murder of Mary.  All these problems stem from Bigger's initial fear that he will be
accused by Mary's mother if she finds him in Mary's bedroom, a fear that is driven by
the institutionalized racism and stereotypes of the time.