In On the Road, we get a glimpse into a friendship based on hero-worship. Sal puts Dean on a pedestal, and in doing so later struggles to feel equal with his friend. The two become uncomfortable when it is clear between them that Sal thinks a great deal of Dean. Defenses are raised on Sal’s part to compensate, and their friendship is momentarily on the rocks. We also look at the intellectual friendship between Carlo and Dean. This friendship is based on mutual interest in each other’s minds.
Sal’s brief fight with Dean underscores the inherent flaws in their relationship, and explains why Sal chooses not to honor their friendship in the end.
Dean, because of his madness, is incapable of being a true friend to Sal. As a result of this limitation, Sal does not hold him morally responsible for his actions.