Maybe generally we are reading about the tragedy of Nadav and Avihu, the two sons of Aharon who died during the inauguration of the Tabernacle, just before the Holocaust Memorial Day, since in both cases it's very hard to understand "why" it happened. Our Sages and Commentators tried to "explain" this tragic event in different ways, probably because we find it difficult to live in a chaotic world, but maybe we really cannot explain or understand "why" personal or collective tragedies happen. All we can do - and maybe that's what our Sages did - is trying to search for meaning in our lives.
I believe that the Shoah could teach us what happens when people start dehumanizing the other or the others; somehow dehumanizing means profaning G!d's image - respecting every human being is a way to be in touch with Divinity.
Shabbat Shalom to all,