The protagonist in All My Sons, Joe is onstage for most of the play. About sixty years old, Joe is not highly educated, but he is a strong, self-made business leader, respected and popular among his neighbors and family, a personification of the postwar American Dream. However, Joe has a sordid secret in his past concerning his own role in a crime that involved allowing his factory to send out faulty airplane engines, resulting in the deaths of American pilots in the war. Joe is not as honest and respectable as he wants to appear, and he is driven by his single-minded desire to provide for his family.

Joe’s true nature, which contrasts dramatically to his outward persona, is slowly revealed over the course of the play. At times, other characters hint at his dishonesty, such as the neighbors who stare when he returns from prison. In Act Two, Sue tells Ann that “Everybody knows Joe pulled a fast one to get out of jail.” Joe denies any responsibility and allows his business partner, Steve Deever, to take the blame. He even faked having the flu on the day the faulty engines were discovered so that he would not be at the plant when they were caulked and shipped. In Act Three, when Ann shares the letter that reveals Larry’s suicide, Joe claims that he did everything to protect his family. He then pretends that he will agree to jail, but because his true nature has been exposed, he kills himself.

Joe Keller cares most about money and family. His downfall represents the downfall of the postwar American culture, which compromised integrity for the sake of monetary and social success. In Act Three, it appears that Joe has finally accepted responsibility. However, the cowardice of his offstage suicide shows that he cannot bear to handle the truth that he has let down his family. He chooses death over honesty and values his own American Dream above personal responsibility.