Herrera was a longtime member of the Communist Party before becoming a FARC rebel. Since joining the guerrillas in the late 1970s, he had built a reputation as a good commander and gained the trust of his troops despite being another comandante de media-carrera, intellectual half-timer from the city. He had also forged a strong relationship with Jacobo Arenas, which paved the way for his rapid ascension in the organization. Now Arenas decided that Herrera was
the man to carry his master plan ahead and move the FARC into the cities through the Unión Patriótica. But first Herrera had to find out who the UP was.