Sergeant Major Cook reported to recruit training at MCRD San Diego, California on 1 August 1994. Upon completion, he received training at the School of Infantry, at Camp Pendleton where he received the MOS 0341, Infantry Mortarman.
Following training at the School of Infantry, Sergeant Major Cook reported to 2d Battalion, 2d Marines in Camp Lejeune, North Carolina. In January 1996, he deployed with the 22d MEU and participated in Operations Joint Endeavor (Bosnia), Assured Response (Liberia) and Quick Response (Central African Republic). He again deployed with the 22d MEU in July 1998.
In March 1999, Sergeant Major Cook was reassigned to Inspector & Instructor Staff, Company L, 3d Bn, 25th Marines in Columbus, Ohio. While there he served as the armory custodian and had many collateral duties.
In April 2002, Sergeant Major Cook was assigned to 2d Bn, 4th Marines, where he served in 81mm Mortar Platoon. In July 2002, he deployed to Okinawa with the 31st MEU. While there, he conducted Operation Foal Eagle in Korea and also trained at Camp Fuji. Upon his return from Okinawa in July 2003, Sergeant Major Cook attended the Infantry Unit Leader’s Course where he graduated as the Honor Graduate. In February 2004, Sergeant Major Cook deployed to Ar Ramadi, Iraq and while there he served as a Mobile Assault Platoon Commander. In September 2004, he was combat meritoriously promoted to the rank of Gunnery Sergeant.
In January 2005, Sergeant Major Cook attended Combat Instructor Course Class 2-05 at SOI, Camp Pendleton. Upon graduation in March, Sergeant Major Cook was assigned as the Chief instructor for Infantry Training Battalion, and later as the Company Gunnery Sergeant, Company A. Sergeant Major Cook ended his tour as a Combat Instructor serving as an instructor at the Infantry Unit Leader’s Course.
Sergeant Major Cook was selected to First Sergeant in December 2007 then frocked in January 2008 and assigned as the Company First Sergeant, Company K, 3d Bn, 1st Marines. He was deployed to Okinawa with the 31st MEU in July 2008. In April 2010, Sergeant Major Cook deployed to Garmsir District, Helmand Province, Afghanistan.
In February 2011, Sergeant Major Cook arrived at Instructor-Inspector Staff, Lexington, KY where he served as the Inspector & Instructor Staff, First Sergeant for Military Police Company “A”, 4th MLG.
In November 2012, Sergeant Major Cook was promoted to his present rank and reported to Recruiting Station Milwaukee to serve as the RS Sergeant Major.
In September 2015, he was reassigned to Headquarters and Service Battalion, United States Marine Corps Forces, Pacific. In December 2017, Sergeant Major Cook transferred to Miami, Florida to become the Command Sergeant Major for HQs U.S. Marine Corps Forces, South located in Doral, Florida.
Sergeant Major Cook’s personal awards include the Legion of Merit, the Meritorious Service Medal with gold star in lieu of second award, the Navy & Marine Corps Commendation Medal w/ Combat Distinguishing Device and two gold stars in lieu of third award, the Navy & Marine Corps Achievement Medal w/three Gold Stars in lieu of fourth award, and the Combat Action Ribbon w/gold star in lieu of second award.