U.S. Air Force Col. Christopher Brooks, U.S. Delegation Chief for the United States, reports in during the opening ceremony of Combined Endeavor 2013.Combined Endeavor 2013 prepares nations to collaborate, plan and execute complex command, control, communications and computers (C4) systems in crisis response and combat operations. The exercise began in 1995 to build partnerships between nations. Nearly 40 NATO, Partnership for Peace and coalition partner nations are represented this year.