Question: Thunderbirds was a film featuring the exploits of what part of the Oklahoma Army National Guard?

Context:
Ohio National Guard
The Ohio National Guard comprises the Ohio Army National Guard and the Ohio Air National Guard.
 The commander-in-chief of the Ohio Army National Guard is the governor of the state of Ohio.
 If the Ohio Army National Guard is called to federal service, then the commander-in-chief becomes the President of the United States.
 The military commander of all forces in the State of Ohio is the Adjutant General, Major General Deborah A. Ashenhurst (the first woman to hold this position) is responsible for the command of 17,000 members, preparedness and readiness, installation management, and budget of the Ohio National Guard.
 The current Assistant Adjutant General for Army, with responsibility for overseeing the Ohio Army National Guard training and operations, is Major General John C. Harris Jr. The current Assistant Adjutant General for Air is Brigadier General Stephen E Markovich, with responsibility for overseeing the Ohio Air National Guard.
New York Army National Guard
The New York Army National Guard is a component of the New York National Guard and the Army National Guard.
 Nationwide, the Army National Guard comprises approximately one half of the US Army's available combat forces and approximately one third of its support organization.
 National coordination of various state National Guard units are maintained through the National Guard Bureau.
Oklahoma Air National Guard
The Oklahoma Air National Guard (OK ANG) is the air force militia of the State of Oklahoma, United States of America.
 It is, along with the Oklahoma Army National Guard, an element of the Oklahoma National Guard.
Illinois Army National Guard
The Illinois Army National Guard is a component of the United States Army and the United States National Guard.
 With the Illinois Air National Guard it is part of the Illinois National Guard.
 National coordination of various state National Guard units are maintained through the National Guard Bureau.
 The Illinois Army National Guard is composed of approximately 10,000 soldiers.
Oklahoma Army National Guard
The Oklahoma Army National Guard is the Army National Guard component of the Oklahoma National Guard.
 The Commander in Chief of the Oklahoma National Guard is the Governor of Oklahoma, who appoints the State Adjutant General (TAG), a Major General from either Army or Air.
 Currently, the TAG is Major General (MG) Robbie L. Asher.
 The previous TAG was Myles Deering MG Deering retired and was appointed Director of Veterans Affairs for the State of Oklahoma.
Thunderbirds (1952 film)
Thunderbirds is a 1952 war film directed by John H. Auer starring John Derek, John Drew Barrymore, Mona Freeman, Gene Evans, Eileen Christy and Ward Bond.
 featuring the exploits of the 45th Infantry Division in the Italian campaign of World War II.
 The film was made by Republic Pictures with sequences filmed at Fort Sill, Oklahoma.
28th Infantry Division (United States)
The 28th Infantry Division ("Keystone") is a unit of the Army National Guard and is the oldest division-sized unit in the armed forces of the United States.
 Some of the units of the division can trace their lineage to Benjamin Franklin's battalion, "The Pennsylvania Associators" (1747-1777).
 The division was officially established in 1879 and was later redesignated as the 28th Division in 1917, after the entry of America into the First World War.
 It is today part of the Pennsylvania Army National Guard, Maryland Army National Guard, Ohio Army National Guard, and New Jersey Army National Guard.
45th Infantry Division (United States)
The 45th Infantry Division was an infantry division of the United States Army, part of the Oklahoma Army National Guard, from 1920 to 1968.
 Headquartered mostly in Oklahoma City, the guardsmen fought in both World War II and the Korean War.
 They trace their lineage from frontier militias that operated in the Southwestern United States throughout the late 1800s.
Kansas Army National Guard
The Kansas Army National Guard is a component of the Army National Guard and the Kansas National Guard.
 Kansas Army National Guard units are trained and equipped as part of the United States Army.
 The same ranks and insignia are used and National Guardsmen are eligible to receive all United States military awards.
 The Kansas Guard also bestows a number of state awards for local services rendered in or to the state of Kansas.
 It is, along with the Kansas Air National Guard, an element of the Kansas National Guard.
189th Field Artillery Regiment (United States)
The 189th Field Artillery Regiment, today consists of 1st Battalion, 189th Field Artillery Regiment, and 2nd Battalion (General Services) Field Artillery Regiment which are headquartered in Oklahoma City, Oklahoma.
 It was a part of the 45th Infantry Division, Oklahoma Army National Guard.
 The Regiment only retains its affiliation with the Field Artillery branch for purposes of history and lineage and is the core cadre and leadership of the Oklahoma Regional Training Institute (OKRTI).
 Its parent unit is the Joint Force Headquarters of the Oklahoma Army National Guard.

Answer: 45th Infantry Division