CARACAS, Venezuela - Venezuela will install an advanced air-defense system with anti-aircraft missiles capable of shooting down approaching enemy warplanes, Venezuelan President Hugo Chavez said Thursday. Chavez, who has repeatedly accused the United States of plotting to overthrow him, said the missiles would help defend the oil-rich country against any "aggression." "We're going to acquire the most modern anti-aircraft defense system," Chavez said during a televised speech in the coastal state of Falcon, where military planes and newly purchased Russian helicopters swooped overhead during a military parade. "We're going to armor Venezuela." He said the air defense system would protect...