Miller dramatizes this in Keller's and Chris's different views about personal and social responsibility. Keller believes that he is only answerable to his family and that his war crimes ought to be excused because he did it to save his family from ruin. Chris, on the other hand, believes in social responsibility - that we must care about society and that we are responsible for the well-being of all members of society.
Miller probably understood Keller's situation well because his own family had lost everything. Through Chris, Miller challenges Keller's values by saying that he should take responsibility for his past actions.
Joe Keller is a typical example of someone who lives the American Dream. He owns a nice house and has a successful business. But in order to keep up this lifestyle, Keller committed a serious crime - he shipped out a batch of faulty cylinder heads to the Air Force, which caused the death of 21 pilots. Then, in order to carryon his way of life, Keller hired the best lawyers in town to get him off the hook. In other words, Arthur Miller is criticizing the values of the
American Dream by suggesting that it can lead to greed, corruption and even murder.
: In the beginning of the play, Chris is presented as an idealist who believes in a higher responsibility to the world at large. He has an idealistic vision of his father. He loves and admires him (he calls him "Joe McGuts") and is very proud of his achievements. However, when he realizes that his father was responsible for the death of 21 pilots, his whole world collapses. Chris turns into a man who is deeply ashamed of himself, because he had suspected his father was guilty but did nothing about it. The new Chris no longer lives by his ideals, nor does he seek justice for the dead pilots. This Chris is practical. Turning his father in won't bring back the dead.