Zinke served as a U.S. Navy SEAL from 1986 to 2008, retiring at the rank of commander.[17] Zinke graduated from Basic Underwater Demolition/SEAL training class 136 in February 1986[3] and subsequently served with SEAL TEAM ONE from 1986 to 1988. His next assignment was as a First Phase Officer of BUD/S before serving with United States Naval Special Warfare Development Group (NSWDG), from May 1991 to 1993.[13][18] Zinke then served as a Plans officer for Commander in Chief, U.S. Naval Forces, Europe (CINCUSNAVEUR) and served a second tour with NSWDG as team leader, ground force commander, task force commander and current operations officer from 1996 to 1999.[13]