You might try the new face recognition softwares with a search of Internet images posted and look at family trees for a Miller Family in Idaho.
http://worldwidegenealogy.blogspot.com/2014/07/genealogy-csi...Also look at Miller Families in 1940 census with a son Raymond, Raymund, Ray or just initial R. Most male WWII Enlistees were born 1914 to 1930. He looks to be 1922 to 1928. If age was 18 before 1941 he might be in his own household as Head or a boarder or laborer in another household in the 1940 census.
His enlistment would have been in the U.S. Army Air Corps if prior to 1942. Then it was referred to as U.S. Army Air Force. The service branch U.S. Air Force didn't begin until Sept 18, 1947.
WWII ended August 1945 so if Miller was discharged before then all Military records or indexes would list branch of service being Army or Army Air Corps.
Online NARA Army Enlistments.
http://aad.archives.gov/aad/series-list.jsp?cat=WR26