President Barack Obama and his wife, Michelle Obama, wave at the crowd as they depart from the 2013 Commander In Chief inaugural ball at the Walter E. Washington Convention Center in Washington, D.C., Jan. 21, 2013. Throughout the 57th Presidential Inauguration, the Obama and Biden families have taken the opportunity to highlight the spirit of service and selflessness seen everyday U.S. military men, women and their families. (U.S. Air Force photo by Chief Master Sgt. Robert W. Valenca/Released)