WASHINGTON (AP) -- Navy Lt. John Kerry knew he had no business steering his Mekong River patrol boat across the border into Cambodia, but orders were orders. A quarter-century later, Sen. John Kerry says newly declassified documents have convinced him fellow servicemen captured on such trips were left behind at war's end. ...But for Kerry, who spent six violent months commanding a patrol boat on the Mekong River, there's always been a ring of truth to allegations of abandoned Americans. By Christmas 1968, part of Kerry's patrol extended across the border of South Vietnam into Cambodia. "We were told, `Just...