BERLIN — When my grandfather died, I was 12 years old. When I tell his story, people often ask if I knew him. For the latest news & views from every corner of the world, Worldcrunch Today is the only truly international newsletter. Sign up here. I remember a small apartment in a new post-war building, I remember a trench coat, strawberries with whipped cream, and the watercolors that he painted. I remember short sentences and a restrained smile. He called me “my little mouse tail.” I suspected that there was some dirt around my grandfather. My father didn’t exactly speak warmly of his father, …