At the outbreak of World War II, he was serving as an advisor to a battalion of the 12th Infantry Regiment, Philippine Commonwealth Army.

Upon the fall of Bataan in April 1942, he evaded capture with his friend Captain Russell W. Volckmann, and until October 1945 conducted the Commonwealth military and guerrilla warfare on the island of Luzon.

[1]: 268, 323 In January 1945, Blackburn established his headquarters in Tuao, building a C-47 airfield, roads, and re-establishing schools and hospitals in the Kalinga, Bontoc, Cagayan and Apayao.

[1]: 286  Blackburn's men supported Sixth United States Army Force B in the capture of Aparri on 20 June 1945.

[1]: 302  Blackburn was awarded the Silver Star after he led his men in the capture of Mayoyao, Ifugao, a stronghold of General Mikami's forces in August 1945.

While in the position, he authorized and oversaw the initial election of the Son Tay POW Camp for Operation Ivory Coast in 1970, briefing General Earle Wheeler, then Chairman of the Joint Chiefs of Staff.

He is the one that chose Air Force BG Leroy J. Manor as overall commander of the raid, Bull Simons, Dick Meadows and "Doc" Cataldo.

[4] He served as the assistant deputy director, Defense Communications Planning Group from August 1966 to August 1967, the assistant division commander, 82nd Airborne Division from September 1967 to October 1968, and the director of plans and programs, office of the Chief of Research and Development from October 1968 until his retirement in 1971.