[4] He previously served as Senior Military Assistant to the United States Secretary of Defense, a position for which he was nominated by James Mattis in September 2018.

[5][6] He was commissioned in 1985 after graduating from the University of North Carolina at Chapel Hill, through a Naval ROTC program.

Smith was commissioned in the United States Marine Corps as a second lieutenant in 1985 following graduation from the NROTC program at the University of North Carolina at Chapel Hill.

He then transferred to 1st Battalion, 3rd Marines, serving as Logistics Officer and Rifle Company Commander.

As a lieutenant colonel, Smith assumed command of 1st Force Reconnaissance Company, during which he deployed twice in support of Operation Iraqi Freedom.