The guerrilla war was not going well for the Viet Cong in the late fifties. Badly needed supplies moving down jungle trails from North Vietnam were constantly being spotted by South Vietnamese warplanes and often destroyed. To give themselves a fighting chance, existing tribal trails through Laos and Cambodia were opened up in 1959. The North Vietnamese went to great lengths to keep this new set of interconnecting trails secret.  The first North Vietnamese sent down the existing tribal trails...