Why Insurgencies Are Hard to Defeat

In 1954, the French garrison at Dien Bien Phu was overrun by a Viet Minh force the French had spent years dismissing as peasants with rifles. Two decades later, helicopters lifted the last American officials off a roof in Saigon. A generation after that, a Soviet column withdrew across the Friendship Bridge from Afghanistan, and twenty-two years later an American convoy retraced essentially the same route. In each case, the stronger party had more men, more firepower, more money, and lost anyway. The pattern is old enough and broad enough to demand a structural explanation rather than a list of tactical mistakes.

An insurgency is a protracted political-military campaign waged by a comparatively weak group that aims to overthrow or expel a ruling power by combining armed action with the cultivation of popular support. The definition matters because it tells you what the insurgent is competing for. The insurgent is not trying to win battles in the conventional sense; battles are usually disastrous for the weaker side. The insurgent is trying to make the cost of governing exceed what the occupying or incumbent power is willing to pay, and to make their own movement appear to a watching population as the more legitimate claimant to authority.

This reframing exposes the first structural problem for the counterinsurgent. The two sides are not playing the same game. A conventional army measures progress by terrain held, enemy killed, and infrastructure built. An insurgent measures progress by political erosion: a district where tax collectors no longer travel at night, a village elder who quietly stops cooperating, a news cycle in the metropole that turns against the war. Many of the counterinsurgent's apparent victories — a cleared province, a high body count — are irrelevant to the contest the insurgent is actually waging.

The second structural problem is the asymmetry of time. Insurgencies are local; the people fighting them live there. The counterinsurgent, especially a foreign one, is on a clock set by domestic politics, budget cycles, and the patience of allied governments. The insurgent need not win in any given year. They need only persist, because every year that passes without resolution is a year in which the counterinsurgent's legitimacy at home erodes. Mao's formulation — that the guerrilla wins by not losing — is a statement about time horizons.

The third structural problem is the asymmetry of costs imposed by force itself. To find insurgents hidden among civilians, the counterinsurgent must search, detain, sometimes kill. Each such action, if mistaken or perceived as unjust, recruits for the other side. The insurgent therefore has an incentive to provoke heavy-handed responses, and the counterinsurgent has no clean way to refuse the bait. This is the dynamic David Galula described as the counterinsurgent fighting with one hand tied — not by squeamishness but by arithmetic. A raid that kills ten fighters and alienates a hundred families is a net loss the body count will not show.

None of this means insurgencies always win. The Malayan Emergency, the Greek Civil War, the defeat of the Tamil Tigers in Sri Lanka, and the suppression of the Huk Rebellion are reminders that insurgencies can be defeated, sometimes by patient political reform, sometimes by methods modern liberal states will not use. Historians continue to argue about which factors were decisive in each case, and the debate is unsettled enough that confident general formulas should be treated with suspicion. What the recurring pattern suggests is more modest: a conventional army facing an insurgency is fighting on terrain it did not choose, on a clock it does not control, with tools that often produce the opposite of their intended effect. Material superiority is real, but it is being asked to do work it was not designed for.