In the previous pages I have tried to discuss the film noir phenomenon rom a cultural perspective, and I am sure you will agree; it is an enormous task. But on the basis of what I have done so far, I will say that the answer to the question asked in the title--Does Film Noir mirror the culture of contemporary America?-- is both positive and negative. Negative in the sense that to use the mirror metaphor in research concerning film and culture is not adequate.
In addition there will never be only one culture stream in a country. There may be a main current, but in postwar America this is difficult to determine.
So, even if film noir does not mirror contemporary American culture, it certainly dealt with subjects closely related to american society at that time.