U.S. Defense Secretary Robert M. Gates thanks German motorcycle police for their assistance in his motorcade in Berlin, April 25, 2007. U.S. Defense Secretary Robert M. Gates thanks German motorcycle police for their assistance in his motorcade in Berlin, April 25, 2007. SHARE: Download: Full Size (1.71 MB) Tags: Photo Essays Credit: VIRIN: 836074-V-NSB02-597.jpg Photo Gallery