US Secretary of Defense Robert Gates (L) greets the People's Republic of China Central Military Commission Vice Chairman General Xu Caihou (R) at the Pentagon in Washington, DC, October 27, 2009. Xu, the highest level Chinese military official to visit in years of rocky relations between the superpowers, holds talks with Gates amid US concerns over China's emergence as a potential high tech military rival. AFP PHOTO/Jim WATSON (Photo credit should read JIM WATSON/AFP/Getty Images)
