COMBINED ARMS U.A. Army Soldiers help Air Force Staff Sgt. Johnathon Krueger across a irrigation canal outside Joint Base Balad, Iraq, during Operation Lewis and Clark Sept. 11, 2008. Operation Lewis and Clark was a joint patrol in which Air Force security forces Airmen were introduced to Balad's outer perimeter. Since Americans began operating from Balad in 2003, the Army has been responsible for base security. SHARE: Download: Full Size (0.07 MB) Credit: VIRIN: 168333-G-INE33-980.jpg Photo Gallery