I can see where it would be really difficult to get your head around the idea of your Opa being involved in that. It's just not how we think about our grandparents.

My Politics teacher engaged in a very interesting experiment to show us how easy it was for people to get swept up. (It's a long story, but I'll tell it if you want me to.) It shocked the hell out of me for its effectiveness, but my classmates...I think it broke their hearts. The difference in their reactions vs. my reaction was astonishing to me.

(Geez, I've been back home for 22 years, and I STILL learn things from my exchange.)