Germany: About 1 fatality per 10,000 cars per year, 4.1 fatalities per billion km driven per year, 38 fatalities per million people per year (2017). Relatively few accidents on the Autobahn, but the proportion of fatal accidents is higher. All in all, the Autobahn is fairly safe, in particular in relation to distance traveled.
USA: About 106 fatalities per million people per year (2013).
I suspect the difference is due to more public transport, less distance driven per person, and possibly more stringent driver education in Germany.
http://apps.who.int/gho/data/node.main.A997
https://www.destatis.de/DE/PresseService/Presse/Pressemittei...