I grew up in a small West German village, Hamm an der Sieg. Without television or computers, my friends and I played outside and acted out adventure and survival stories. This daily practice taught me not to be afraid of physical encounters, and I developed a capacity for quick thinking and action. I didn’t know how useful that would turn out to be.
At 16, my mother and I moved to the large city of Hamburg. In the West Germany of the 1970s, motorcycle gangs started to appear and at…