Why would Elie Wiesel be passionate about promoting peace and understanding in our world?

Because he was a person who witnessed the atrocities of the holocaust and knows that it was caused by intolerance and violence among people.

Explanation:

Wiesel was a holocaust survivor. He witnessed all the violence and intolerance that almost decimated the Jews and was responsible for the torture and murder of thousands of them.

Wiesel recognizes that the holocaust happened due to intolerance, violence and prejudice. As he recognizes how destructive these factors can be, he has dedicated his life to promoting peace, tolerance and an understanding of the differences between people, races and religions around the world.

His work was so important that it allowed him to be awarded the Nobel Peace Prize.