This study tested conventional wisdom about how insurgencies end against the evidence from 89 insurgencies. It compares a quantitative and qualitative analysis of 89 insurgency case studies with lessons from insurgency and counterinsurgency (COIN) literature. While no two insurgencies are the same, the authors find that modern insurgencies last about ten years and that a government's chances of winning may increase slightly over time. Insurgencies are suited to hierarchical organization and rural terrain, and sanctuary is vital to insurgents. Insurgent use of terrorism often backfires, and withdrawal of state sponsorship can cripple an insurgency, typically leading to its defeat. Inconsistent support to either side generally presages defeat for that side, although weak insurgencies can still win. Anocracies (pseudodemocracies) rarely succeed against insurgencies. Historically derived force ratios are neither accurate nor predictive, and civil defense forces are very useful for both sides. Key indicators of possible trends and tipping points in an insurgency include changes in desertions, defections, and the flow of information to the COIN effort. The more parties in an insurgency, the more likely it is to have a complex and protracted ending. There are no COIN shortcuts.

The research described in this report was prepared for the Marine Corps Intelligence Activity. The research was conducted in the RAND National Defense Research Institute, a federally funded research and development center sponsored by the Office of the Secretary of Defense, the Joint Staff, the Unified Combatant Commands, the Department of the Navy, the Marine Corps, the defense agencies, and the defense Intelligence Community.

This report is part of the RAND Corporation monograph series. RAND monographs present major research findings that address the challenges facing the public and private sectors. All RAND monographs undergo rigorous peer review to ensure high standards for research quality and objectivity.

Permission is given to duplicate this electronic document for personal use only, as long as it is unaltered and complete. Copies may not be duplicated for commercial purposes. Unauthorized posting of RAND PDFs to a non-RAND Web site is prohibited. RAND PDFs are protected under copyright law. For information on reprint and linking permissions, please visit the RAND Permissions page.

The RAND Corporation is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND's publications do not necessarily reflect the opinions of its research clients and sponsors.