In 1943 Judge Green enlisted in the United States Army Air Corps, the predecessor to the United States Air Force. At the time, the armed forces were still segregated. Green was initially "optimistic that the military was going to be a good life," until his unit was shipped from Fort Lee, Virginia to Keesler Field (now Keesler Air Force Base), in Mississippi. When the unit arrived at Keesler they were driven past the barracks to what Green would later describe as "a tent city." It was then that Green "realized for real that I was really in a segregated army, and there was always, as long as I was in the service, two standards, one quite unacceptable and the other as acceptable as could be considering the fact that the country was at war."