VENEZUELAN military officers have started classes in unconventional warfare to repel an invasion left-wing President Hugo Chavez warns Washington is planning. Snipers draped in foliage and civilian reservists armed with knives, catapults and handguns crawled out of a hidden tunnel in a mock demonstration as an instructor lectured officers on resistance tactics. Captains joined lieutenants straining behind a cordon to see another soldier camouflaged inside tree perch as he fired a bow and peppered a uniformed dummy target with arrows. "If no one comes, then that's fine, we can continue as the free and sovereign country we are, but we...