Carter Hosts 'Big 4' Meeting at Pentagon Incoming Defense Secretary Ash Carter hosts a "Big 4” round-table meeting with Deputy Defense Secretary Bob Work, right, Army Gen. Martin E. Dempsey, left, chairman of the Joint Chiefs of Staff, and Navy Adm. James A. Winnefeld Jr., vice chairman of the Joint Chiefs of Staff, at the Pentagon, Feb. 17, 2015, as Carter assumed his new duties. SHARE: Download: Full Size (0.07 MB) Credit: VIRIN: 663013-A-GZI14-414.jpg Photo Gallery