Through his service, Robertson became known as the “Father of the Air National Guard” in Missouri. He served in the Army Air Service in World War I. After the war, he co-founded Robertson Aircraft Corporation in St. Louis and worked with Albert Bond Lambert to establish Lambert-St. Louis Field.
The 35th Division Aviation, Missouri National Guard, was organized in St. Louis on June 23, 1923, when the 110th Observation Squadron, 110th Photo Section and 170th Intelligence Section were federally recognized and designated as components of the 35th Division Air Service. Robertson served as the first commanding officer of the 35th Division Air Service.
In 1943, Robertson, along with St. Louis Mayor William Becker and eight others, was killed when a glider crashed at Lambert-St. Louis Field during a flight demonstration.