The "Founding Fathers of Armor" were photographed at Fort Knox in 1938. Standing in the forefront are Col. Charles Scott, Maj. Gen. Daniel Van Voorhis and Brig. Gen. Adna Chaffee Jr. All three were intimately involved in the development of mechanized cavalry and the armored force, and all three would serve as commanding generals at Fort Knox during their careers.

Later that same year, Chaffee showed a 75mm howitzer to then-Senator Harry S. Truman during a visit in November. Truman, a member of the Appropriations Committee, served as an artillery captain during the First World War. It was his second visit to the installation that year, having visited with other government officials in January.

Truman became President of the United States April 12, 1945, following the death of President Franklin D. Roosevelt.