His strategical studies of the islands over a three-year period developed knowledge he used later when he returned to the Philippines in 1944 as Chief Engineer of General Walter Krueger's Sixth U.S. Army.

Sturgis commanded a mounted engineer company at Fort Riley, Kansas, in 1929–1933 and encouraged the adoption of heavy mechanical equipment.

After assignments in Eastport, Maine and Huntington, West Virginia,[5] Sturgis graduated from the Army War College in June 1940.

[6] He was then district engineer in 1940–1942 for Vicksburg, Mississippi, where he worked on flood control and a large military construction program.

During World War II, Sturgis' engineer troops built roads, airfields, ports, and bases from New Guinea to the Philippines.