Pfc. Juan Fordona of Puerto Rico, a First Cavalry Division trooper, shakes hands with U.S. Marine Cpl. James Hellebuick over barbed wire at the perimeter of the Marine base at Khe Sanh, South Vietnam, early April 1968. The meeting marked the first overland link-up between troops of the 1st Cavalry and the encircled Marine garrison at Khe Sanh. (AP Photo/Holloway)