Sergeant Major Jacobsen reported to MCRD Parris Island SC on 4 September 2002, to 1st Recruit Training Battalion, Company A, Platoon 1102. Upon graduation in late November 2002, he was ordered to report to Marine Combat Training East, Camp Geiger, NC, in January 2003. Graduating in February 2003, Sergeant Major Jacobsen received orders to Aberdeen, Maryland where he went through Small Arms repairman School until he received orders in May 2003.
In May 2003, he reported to Marine Corps Security Company, Bahrain, where he was assigned as the Armory Chief, Headquarters and Service Company. Once promoted to the rank of corporal meritoriously, he received orders to report to Marine Corps Combat Service Support Schools Camp Johnson, NC. He was assigned as the Armory Chief, Headquarters and Service Company. In 2004, he was meritoriously promoted to the rank of sergeant, where he submitted an SDA package to become a Drill Instructor and was then given orders to report to MCRD Parris Island, SC Drill Instructor School.
In June 2006 he graduated from DI School and was assigned to 1st Recruit Training Battalion, Company A. He was meritoriously promoted to Staff Sergeant in July 2008. After a successful tour on Drill Instructor duty, he requested orders to 3d Battalion 8th Marines, Camp Lejeune, NC.
In 2010 he deployed with the 24th MEU ending his deployment in Helmand providence, Afghanistan as the battalion Armory Chief. After his meritorious promotion to GySgt, he once again deployed in 2012 as the S4 Chief to Camp Geronimo, Afghanistan in support of the Battalion combat operations. Soon after completing the deployment in 2013, he requested orders to the Staff Noncommissioned Officer Academy Camp Johnson, NC. During his time with the Academy, Sergeant Major Jacobsen became the Chief faculty Advisor for the Advance Course and the SNCOIC for the Corporals Course. At the end of his time with the Academy he was selected to First Sergeant and requested orders to 3D Battalion 6TH Marines.
Sergeant Major Jacobsen received PCS orders in March 2016 to 3d Battalion, 6th Marines where he served as the Company First Sergeant for Company K. In 2017 he deployed in support of the 26 MEU aboard the USS Carter Hall. Upon his return he received orders to 4th Marine Division, Delta Company Inspector Instructor First Sergeant in Albuquerque, New Mexico. In February of 2021 he was promoted to the rank of Sergeant Major and served as the Command Senior Enlisted Leader for 2d Radio Battalion II Marine Information Group and is currently serving as the Command Senior Enlisted Leader for Marine Heavy Helicopter Squadron 461, Marine Aircraft Group 29.
His personal awards include: The Meritorious Service Medal w/1 Gold star in lieu of second award, Navy Commendation Medal w/1 Gold star in lieu of second award, Navy and Marine Corps Achievement Medal w/2 Gold star’s in lieu of third award.