[1][2] However, the Army Air Forces found that standard military units, based on relatively inflexible tables of organization, were proving poorly adapted to the training mission.

Accordingly, it adopted a more functional system in which each base was organized into a separate numbered unit,[4] while the groups and squadrons acting as RTUs were disbanded or inactivated.

The squadron was equipped with the North American F-51D Mustang and was assigned to the 128th Fighter Group of the Wisconsin Air National Guard.

At Bergstrom, its mission was to replace the 27th Fighter-Escort Group which deployed to Japan as part of Strategic Air Command's commitment to the Korean War.

At George, the unit was scheduled to be re-equipped with Republic F-84D Thunderjets for deployment to Japan, however the F-84s were instead sent to France and the squadron remained in California with Mustangs for the remainder of its federal service.

The 170th remained at Springfield, while elements of the 131st deployed to Toul-Rosières Air Base, France to form the 7131st Tactical Fighter Wing.

While in France, the Guardsmen trained with elements of the United States Seventh Army and maintained a 24-hour alert status.

All F-84Fs were grounded in November 1971, after a 170th pilot was killed when his plane lost a wing during exercises at the Hardwood Gunnery range in Findley, Wisconsin.

The 170th flew the Thunderstreak for more than a decade and a half, longer than any other squadron in the active force or the Air National Guard.

The 170th saw its first General Dynamics F-16A Fighting Falcon on 7 June 1989 when two landed at Capital Airport to replace the squadron's aging F-4D Phantom IIs.

During the 1990s, the unit conducted numerous overseas deployments, including six to Southwest Asia, two to Denmark, one to Panama, one to Curaçao, and one to Thailand.

Starting in January 2002 the 170th deployed for two weeks to Tucson Air National Guard Base, Arizona for final training with the LITENING pod.

The March 2002 deployment was to be with two other units but this changed due to their Operation Noble Eagle air defense commitments.

Besides its duties over Afghanistan, the 170th Expeditionary Squadron performed air interdiction missions over Iraq in support of Operation Southern Watch.

Despite a court challenge by the Governor of Illinois, the US District Judge ruled that there was not enough evidence to support the claim that the state would suffer major harm by the closure of the unit.