There's a big qualifier to all of the tactics described by Che's Guevara's Guerrilla Warfare: that without sufficient support from the masses, none of them can be applied, and if one tries to apply them they'll at best end up running in an endless circle of skirmishes with the state. To gain this level of support, we must understand the conditions that we're operating within. Which is tied in with that requirement of avoiding adventurism, because both adventurism and poor understanding of conditions stem from the same error: lax theoretical study.
An example of this is the failed insurgency of the Shining Path, Peru's Maoist guerrilla organization. What led to the excessive violence that lost the Maoists the support of the masses, and that gave anti-communist propagandists an opportunity to believably exaggerate the abuses of the guerrillas, was the dogmatic approach that they took in attempting their People's War. They sought to impose an inflexible governing model upon the zones they controlled, which led to avoidable clashes with people they could otherwise have gotten on their side. Their insistence on replacing tribal governing structures, despite these structures having worked for millennia beforehand, provoked indigenous opposition. This helped undo their insurgency.
A current example, not coincidentally, also comes from Maoism: in the Philippines, the Maoist guerrillas stick to an outdated line which claims that communists should only ally with the rural population and ignore the urban proletariat. This approach was arguably defensible in the 60s, but as is so often the case for Maoists, they've remained entrenched in a decades-old series of stances that lead to unnecessary antagonism. Their organization has experienced schisms specifically over this debate of whether to reach out to the urban proletariat. People within the zones they've "liberated" often betray them out of self-interest, because their narrow approach has made it needlessly hard for the guerrillas to earn the loyalty of much of even the rural population.
Their related hostility towards China's supposed "social imperialism" has led them to start attacking the Chinese firms which are helping the nation develop a new level of infrastructure, further setting back their potential to bring the masses demonstrable material benefits. There's a reason why it's Filipino communists who've won me over towards not supporting their country's guerrilla forces: these forces may have military power, but this turns into a double-edged sword without proper ideological guidance. The same is being proven by the Naxalite Maoist guerrillas in India, which have embraced a parallel adventurist approach and have also found themselves fighting an unwinnable war.
To avoid such a fate, we must learn to discern between the helpful parts of Che's guide to guerrilla warfare, and the parts that can lead us astray due to their omitting the theoretical details required for gaining adequate mass backing. An example of the latter is this section:
At the outset there is a more or less homogeneous group, with some arms, that devotes itself almost exclusively to hiding in the wildest and most inaccessible places, making little contact with the peasants. It strikes a fortunate blow and its fame grows. A few peasants, dispossessed of their land or engaged in a struggle to conserve it and young idealists of other classes join the nucleus; it acquires greater audacity and starts to operate in inhabited places, making more contact with the people of the zone; it repeats attacks, always fleeing after making them; suddenly it engages in combat with some column or other and destroys its vanguard. Men continue to join it; it has increased in number, but its organization remains exactly the same; its caution diminishes, and it ventures into more populous zones.
Che was correct in this assessment, but he then went on to carry out Focoism, a model that lacks the mass basis which is required for such a revolt. Like the approaches of the Shining Path, the Philippine Maoists, or the Naxalites, Focoism is an angle that's encouraged the guerrillas to act out of step with the masses. Its assumption that an army from a foreign land can win a revolution, despite being made up of fighters who haven't had time to directly study the conditions they're operating within, is self-defeating. As Lin Piao wrote in Long Live the Victory of People's War: "The liberation of the masses is accomplished by the masses themselves - this is a basic principle of Marxism-Leninism. Revolution or people's war in any country is the business of the masses in that country and should be carried out primarily by their own efforts; there is no other way." In his 1969 critique of focoism, Jim Dann says about that quote:
The truth of this statement becomes clear when we examine the relative forces in a revolutionary situation. The class enemy retains superiority in numbers of armed men and in weaponry until the last battle. Despite serious study of military tactics, the enemy may often prove superior in his knowledge of the purely military aspects of war - he's been at it longer. To this "superiority," the revolutionary forces answer with the inexhaustible power of the working people. Their labor, organized into a fighting force behind the revolutionary outlook of seizing state power and establishing the dictatorship of the working class, can bring down the entire imperialist structure. Their strength is crucial. This means that no outside army can make a socialist revolution for the masses, or sustain it for very long if it attempts to. Unless the masses themselves make the revolution, it will eventually fail. Working people throughout the imperialist world are taught that they are powerless, cannot think, and must depend on "great leaders." But the workers will learn to produce their own leaders, to rely on their own resources and labor, and to make their revolution.
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