This is a part from Elie Wiesel's Nobel lecture and he is talking about the memory of the Holocaust and the Second World War as Wiesel was a survivor of the Holocaust and the Nazi prosecution. He believes that the past will serve as reminder and a shield so the horrors he and others went through would never repeat.
There are many reasons why the North and the South had grown so far apart by 1861, but the best option is "A. The North opposed the idea that a state could leave the Union, but the South supported it."
