My parents were children in Europe as the Holocaust was brewing. Their parents, my grandparents, got them out in time so that they could meet in Brooklyn, get married and have children, including me of course. My paternal grandfather told me, when I was a little kid, in his heavy Russian accent "Daveeed, when the Nazis come (he was sure they would) you get a gun and go on the roof and you shoot them!" My parents were horrified. I thought he was just a crazy old man. But he was a lot smarter and wiser than we gave him credit for.