His neighbor, a woman who had lived in the same community with him all his life, shouted out to the Nazi soldiers. Hersch Altman was 11 years old, hiding with his older sister. His Polish neighbor pointed them out. He got away. His sister did not. Hersch never saw her again.

There are tens of millions of stories just like that one. You can change the names, the places, the regimes, and the ethnicity of those involved. Yet the same thing has played out again and again.