Insurgent Success Rates — Boot's Database Findings
Quantifying the History of Irregular War
Boot's most distinctive contribution to the study of insurgency is methodological: he built a database of 443 insurgencies since 1775 and coded each for outcome, duration, ideology type, external support, and other variables. The database is the empirical spine of Invisible Armies — it allows him to make statistical claims about insurgency patterns rather than just reasoning from selected case studies. Every major lesson in the "Implications" section is grounded in what the database shows.
This page is a reference artifact summarizing the database's headline findings. For the causal analysis behind each finding, see the individual concept pages.1
Core Outcome Statistics
Overall insurgent success rate (1775–2013): 25.5% Overall incumbent/counterinsurgent success rate: 63.6% Draws/stalemates: 10.8%
Post-1945 insurgent success rate: 40.3% Post-1945 incumbent success rate: 50.8%
The post-1945 shift is the most significant pattern in the data. Insurgencies became substantially more likely to succeed after World War II — not because guerrilla tactics improved but because the international legitimacy environment changed (decolonization norms, UN system, international media) and because public opinion in democratic counterinsurgent states became a more decisive variable.1
Duration Statistics
Average duration of insurgency since 1775: approximately 10 years Average duration post-1945: approximately 14 years
The longer post-1945 average reflects both the more complex political environments of decolonization conflicts and the fact that external support — which became more available post-1945 — prolonged insurgencies that would otherwise have collapsed.1
Correlation Variables
Boot identifies several variables with the strongest correlation with insurgency outcomes:
Highest correlation with insurgent success:
- External support (safe havens, arms, money, conventional military backup from patron state)
- Government illegitimacy in the eyes of the contested population
- Nationalist ideological foundation
Highest correlation with counterinsurgent success:
- Indigenous government legitimacy
- Disruption of external support to insurgents
- Population-centric doctrine applied with political will and sufficient duration
Variables with weaker-than-expected correlation:
- Terrain (mountains, jungles) — helps insurgents but is not decisive without political support
- Military technology advantage — surprisingly low correlation with outcome
- Raw body count / attrition rate — nearly uncorrelated with outcome1
Historical Era Breakdown
| Era | Insurgent Success Rate | Notes |
|---|---|---|
| 1775–1850 | ~20% | Colonial-era; European powers at peak capacity |
| 1850–1914 | ~15% | Imperial expansion; counterinsurgent technological advantage maximized |
| 1914–1945 | ~25% | WWI/WWII resistance movements; mixed outcomes |
| 1945–1975 | ~45% | Decolonization peak; highest insurgent success era |
| 1975–2013 | ~35% | Post-decolonization; partial return to counterinsurgent advantage |
The decolonization peak (1945–1975) explains much of the romantic narrative around guerrilla warfare's effectiveness. This was a historically anomalous period when colonial powers were simultaneously militarily superior and politically unable to absorb the legitimacy costs of continued colonial rule. The lesson generalized from this era ("guerrillas always win") is historically specific.1
Ideology Type and Success Rate
Boot's data does not provide precise numbers by ideology type, but his qualitative analysis identifies patterns:
- Nationalist insurgencies: Highest success rate among ideological types; renewable legitimacy, international sympathy during decolonization era
- Communist insurgencies: High success rate 1945–1975 when backed by Soviet/Chinese support; declined sharply after Cold War ended and patron support dried up
- Jihadist insurgencies: Too recent and ongoing for definitive statistical assessment; initial successes (Afghanistan, early ISIS territorial gains) followed by significant reversals
- Anarchist/far-left Western insurgencies: Near-zero success rate; no nationalist foundation, no mass popular support1
The "Dying" Trend in Contemporary Insurgency
Boot notes a pattern in his most recent data: the era of successful insurgencies may be entering decline. Post-Cold War, with the Soviet patron no longer available, and with democratic counterinsurgents developing better population-centric doctrine, the insurgent success rate has declined from the 1945–1975 peak.
This claim is highly contested and the most temporally sensitive in Boot's database. The Arab Spring, the Syrian civil war, ISIS's territorial state, the Taliban's return to power in Afghanistan — all post-date the 2012/2013 writing of Invisible Armies and suggest the "insurgency declining" trend was premature.
Methodological Limitations
Boot is transparent about the database's limitations:
Coding decisions are contestable: What counts as an "insurgency"? What counts as "success"? The border between a successful insurgency and a civil war, between a failed insurgency and an ongoing one, involves judgment calls that other scholars might make differently.
Selection bias in historical record: Insurgencies that left significant historical records (primarily those in conflicts that Western powers fought or documented) are overrepresented. Many pre-20th-century insurgencies in Africa, Asia, and the Americas that were suppressed quickly and left minimal documentation are absent.
The 1775 start date: Boot begins in 1775 because data quality improves significantly there. The long history of pre-1775 insurgency is addressed in qualitative chapters but not in the database, which limits the statistical generalizability of pre-modern claims.1
Cross-Domain Handshakes
Propaganda Model — Worthy vs. Unworthy Victims (Cross-Domain): The database's finding that international legitimacy environment drives post-1945 success rates connects to Chomsky and Herman's analysis of how media systems construct worthy vs. unworthy victims. Insurgencies that fit the dominant legitimacy narrative (anti-colonial, nationalist) get "worthy" media coverage that amplifies their external support; insurgencies that don't fit get "unworthy" coverage that doesn't. The database pattern that nationalist insurgencies succeed more often than ideological ones is partly a media effect — nationalist insurgencies are better at generating the "worthy victim" framing.
Arthashastra — State Enterprises (History): Arthashastra — State Enterprises — Kautilya's analysis of the state's economic organization as a resource mobilization system maps onto Boot's external support variable. States that can efficiently extract resources and convert them into military capacity (patron states) can fund insurgencies at scale. States with weak resource extraction capacity cannot. The database finding that external support is the highest-correlation variable with insurgent success is partly a story about state economic capacity on the patron side.
The Live Edge
The Sharpest Implication The database's most counterintuitive finding is the weakness of the body-count correlation with outcome. Military establishments throughout history have measured success through enemy attrition — if we kill enough of them, they'll stop fighting. Boot's data shows this logic is empirically weak in counterinsurgency: the kill ratio predicts outcome less than legitimacy variables, external support, and doctrine type. If the kill metric doesn't predict success, optimizing for it is optimizing the wrong variable. The entire incentive structure of conventional military performance measurement (promotion based on operational success, measured through enemy kills and area cleared) may be systematically selecting for the wrong outcomes in COIN contexts.
Generative Questions
- Boot's database ends in 2013. Post-2013, we have the Taliban return to power, ISIS territorial state and collapse, Houthi sustained campaign in Yemen, and various African Sahel insurgencies. Does this post-2013 data change the trends Boot identifies — or confirm them?
Connected Concepts
- Guerrilla Paradox — why 25% success despite tactical logic
- Outside Support as Success Factor — the highest-correlation variable
- Legitimacy as Critical Factor — the second most predictive variable
- Long Duration — Timeframe Factor — duration statistics from the database