 He continued to speak in favor of the horse and co-authored "The Story of the U.S. Cavalry" (1953).Historians' assessment of Herr's four-year service as Chief of Cavalry range from "stubborn obstructionist" (Hofmann), "conservative and downright mossback" (Millett), "diehard proponent of the horse" (Winton and Mets) to "noble and tragic in his loyalty to horse ... and refusal to accept reality after Munich.