In his thirty years in the Marine Corps, T. X. Hammes served at all levels in the operating forces to include command of a rifle company, weapons company, intelligence company, infantry battalion and the Chemical Biological Incident Response Force. His staff billets include regimental and division intelligence officer; regimental logistics officer; division G-3 operations officer; division G-3 training officer; division, fleet, and expeditionary force plans officer. During his time in the operating forces, he participated in stabilization operations in Somalia and Iraq as well as training insurgents in various places.Hammes is the author of "The Sling and the Stone: On War in the Twenty-First Century" and over 80 articles and opinion pieces.