While at the university he became an active member of the National Society of Pershing Rifles, an ROTC military fraternal organization known for including many who later became successful Army officers.

Following his command at the Ranger Training Brigade, Jackman served as the Director of Combined Arms and Tactics at the United States Army Infantry School at Fort Benning, as well as the Deputy J3 for Training and Readiness, United States Pacific Command (USPACOM), Hawaii.

He was then assigned as Chief of Staff, 10th Mountain Division (Light Infantry), Fort Drum, New York, during which he participated as part of NATO's "Follow-on Force" in Operation Joint Forge, Bosnia-Herzegovina.

Jackman served as Director of Operations, United States Southern Command (USSOUTHCOM) from 2001 to 2003, concentrating mostly on anti-drug and anti-terrorism endeavours.

While in this dual command capacity, Jackman organized the proceedings and security for the dedication of the World War II Memorial on the National Mall and its accompanying WWII reunion, organized former President Ronald Reagan's state funeral, served as the official escort to the former President's wife, former First Lady Nancy Reagan, and served as commander of the Joint Task Force-Armed Forces Inaugural Committee for President George W. Bush's 2005 Presidential Inauguration.

[2] Cathy Jackman is originally from Fayetteville, North Carolina, and is a 1970 graduate of Terry Sanford High School.

In 1983, Jackman graduated after attending the US Army Command and General Staff College at Fort Leavenworth, Kansas, after nearly a year of study.

Finally, Jackman attended the Industrial College of the Armed Forces, (Ft. Lesley J. McNair in SW Washington, D.C.), completing his year-long studies in 1992.