Mattis Remarks Defense Secretary James N. Mattis and Marine Corps Gen. Joe Dunford, the chairman of the Joint Chiefs of Staff, update reporters on the effort to defeat of the Islamic State of Iraq and Syria during a joint news conference at the Pentagon, May 19, 2017. DoD photo by Army Sgt. Amber I. Smith SHARE: Download: Full Size (1.17 MB) Tags: Marines, Briefings, Chairman, SecDef, Joint Chiefs, Inherent Resolve, JIM MATTIS, Joe Dunford, Marine Corps Credit: Amber I. Smith VIRIN: 170519-D-SV709-137.JPG Photo Gallery