Larry David Grathwohl (October 13, 1947 â July 18, 2013) was a United States Army veteran and a Federal Bureau of Investigation informant in the 1970s. He infiltrated the Weather Underground and co-wrote a book about his experiences: Bringing Down America: An FBI informer with the Weathermen (1976).
Grathwohl was in the 2<sup>nd</sup> Battalion, 502<sup>nd</sup> Regiment, 101<sup>st</sup> Airborne Division from 1965 to 1966 and served in the Vietnam War. He became a sergeant.