[1] Hertling served in Armor, Cavalry, planning, operations and training positions, and commanded every organization from Platoon to Field Army.

[2] He also acts as a senior advisor to "Mission Readiness", a nonprofit, bipartisan organization of retired military leaders who call for smart investments for U.S. children.

He has served as a board member for World TEAM (The Exceptional Athlete Matters) Sport, an organization providing opportunities for physically challenged athletes, and he serves as a senior advisor to "Operation Gratitude", an organization supporting deployed military, first line responders, healthcare workers and their families.

In 1975, Hertling was commissioned as a second lieutenant in the Armor Branch after graduation from the United States Military Academy at West Point.

While at West Point, Hertling was on the NCAA Division I Swimming and Water Polo Team, and he was active as a member of his class committee and attained the rank of Cadet Captain.

Throughout his military career, Hertling saw alternating assignment between operational and training postings, and he gained a reputation as a skilled trainer and a soldier-focused leader and commander.

In 1988, he returned to Europe as a major, serving first on the staff of the 1st Armored Division as the deputy G-3, then as the S-3 of 1st Squadron, 1st Cavalry Regiment (Blackhawks) with whom he deployed during Operation Desert Shield/Desert Storm.

In Iraq, Task Force Iron was based in Tikrit, and cooperated with five Iraqi Army divisions in security and on a "whole of government" approach.

[5] Hertling also taught in the Department of Physical Education at the United States Military Academy, and served as a speechwriter for General Frederick M. Franks Jr. when he commanded TRADOC.