WASHINGTON -- No one can be sure who controls the Libyan government's weapons stockpiles, a stew of deadly chemicals, raw nuclear material and some 30,000 shoulder-fired rockets that officials fear could fall into terrorists' hands in the chaos of Moammar Gadhafi's downfall or afterward.One immediate worry, U.S. intelligence and military officials say, is that Gadhafi might use the weapons to make a last stand.