6 ideas
Guerrilla war cannot succeed without the sympathy, cooperation, and active participation of the population, so political organisation of the people comes first and military action rests on it. Without a clear political goal that the masses share, irregular fighting collapses into banditry and loses the support it depends on.
The people are the water and the guerrillas are the fish that live in it: the population gives cover, supplies, recruits, and intelligence. Disciplined, respectful treatment of civilians is a military necessity rather than a moral extra, because alienating the people drains the water the fighters need to survive.
A weaker side facing a stronger invader gives up territory rather than defending it, stretching the enemy's lines and garrisons across ground it cannot fully hold. The time gained is used to build forces and erode enemy strength and morale, turning a long war into an advantage for the side that cannot win quickly.
Guerrillas avoid set-piece engagements against superior forces and strike only where they can concentrate local superiority, using surprise, ambush, and raid. The formula runs: enemy advances, we retreat; enemy halts, we harass; enemy tires, we attack; enemy retreats, we pursue.
Irregular warfare is an auxiliary to conventional operations and must be coordinated with regular forces toward a common strategic aim. Guerrilla units wear down, distract, and disperse the enemy, but final victory needs a shift to mobile and regular warfare once the balance of forces changes.
Viewed through the guerrilla lens, a large conventional army's size becomes a liability: long supply lines, rear areas, garrisons, and dependence on roads are exposed targets. The weaker side stops asking how to match enemy strength and instead asks where that strength leaves the enemy thin, slow, or overextended.