What is the theme in Guerrilla Warfare by Ernesto Guevara?

One of the key themes that run through all of Che's work on guerilla warfare is the need for the guerilla fighter to be both a combatant and a social reformer. This idea is bound up with the realities of actual guerilla warfare as well as with Che's unique ideas about communist revolution. According to traditional Marxists-Leninist theory, communist revolution can only occur in societies that have developed a substantial market economy, enough to generate a large urban working class.