After the September 11 attacks , Hunter joined the United States Marine Corps . He attended Officer Candidates School at Marine Corps Base Quantico ; when he graduated in March 2002 , he was commissioned as a second lieutenant . He subsequently served as a field artillery officer in the 1st Marine Division after the 2003 invasion of Iraq and completed a second tour in Fallujah , Iraq , in 2004 , serving in Battery A , 1st Battalion , 11th Marines . During his second tour , he participated in Operation Vigilant Resolve , where he fought in battles in Fallujah
September 11 attacks
September 11 attacks
Duncan D. Hunter