Does the discovery of the Holocaust emphasize the differences between the Jewish sects, or, instead, minimize the differences?

Interesting question. I would argue that the news of the Holocaust further emphasizes the differences between the groups. The responses of Reb Saunders and David malter to the news of the Holocaust are sharply different and move the direction of their lives and the lives of Danny and Reuven in very different directions. Instead of uniting the sects into one group responding to the horror, the news seems to separate them even more. David Malter becomes a very public figure in the Zionism movement while Reb Saunders retreats into the culture of suffering for his people and drives a wedge between Reuven and Danny.