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The Owl in the Olive Tree | Jan. 17, 2019

Engaging Overseas: Lessons for Afghanistan and Beyond

By Eli Berman and Jacob N. Shapiro

President Trump’s announcement of further troop reductions in Afghanistan raises a substantive question. To what end are US forces engaged at all, after 17 years of a conflict that remains unresolved?

Some argue that we should exit interminable conflicts in fragile states because we cannot win. When we try to be the world’s nation builder, mediator, and police force, the result is costly and often counterproductive. Others argue that we must intervene because we can do something and that developed democracies have a moral obligation to work toward stability in struggling nations.

Both views are wrong. In some situations, doing the things we can do will make a real difference at a cost we are willing to absorb. In other situations, it will not.

So how do we know the difference? And in which category does Afghanistan belong? Our research at the Empirical Studies of Conflict (ESOC) project has revealed a cost-effective type of intervention that can stabilize regions in a country suffering civil war. The decision to employ such strategies, however, must be premised on a realistic prognosis of what can be achieved. This will help avoid costly premature exits, as occurred in Iraq; costly non-interventions, such as Libya; and disappointing open-ended engagements, such as Afghanistan.

Being Realistic: Facts about Small Wars
A first step is to notice how military engagements have changed. Small, subnational wars have been the prevalent form of conflict for decades. Historical evidence indicates that a clear priority of foreign policy of the U.S. and other developed nations since World War II has been to bring order to countries that have fallen into conflict. Many early interventions were expressions of Cold War competition or aftershocks of colonialism, but even since the end of the Cold War, the United Nations, NATO, and other regional bodies continue to intervene in civil conflicts. The accumulated number of interventions is growing, as we see below in a figure from chapter 1 of our book, Small Wars, Big Data: The Information Revolution in Modern Conflict.

Figure 1: Trends in foreign military interventions by the United States and NATO since 1975.  Figure on the left denotes the number of new overseas interventions starting in a given year involving the United States alone, the United States as part of a coalition force, or NATO. Figure on the right depicts the number of ongoing interventions in each year (i.e., the total number for which some portion of the conflict took place in that year), starting with conflicts beginning in 1975. All data are from the IMI data set (Pickering and Kisangani 2009).

Many of these recent interventions are in conflicts which take a long time to resolve. The average civil war now lasts about a decade. And most of these conflicts are asymmetric in the sense that one side (usually the government) has a clear advantage in fire power and legitimacy. Yet the weak side in those conflicts is often entrenched in its territory, with a source of financial resources and enough popular support to disappear among civilians, so that it can force a stalemate or even gain ground.

Despite rhetoric to the contrary, the United States and its allies will likely continue to intervene in other countries’ subnational conflicts. This has less to do with the West’s charity than with its self-interest. Small wars such as those in Syria, or Libya, tend to spill over borders and contribute to international instability. They can incubate militant groups who conduct terrorist attacks in the West. Moreover, small wars leave ungoverned (or improperly governed) spaces that breed a range of other threats, such as drug trafficking and human trafficking, as in Afghanistan and Mexico, and infectious diseases such as Ebola, as in West Africa. Small wars also have the potential to catalyze regional wars, as powerful nations intervene on one side or another, as might still occur in Syria.

Winning the Village: Patient, Limited Force Intervention
Importantly, we know how to win villages, valleys, and districts. In Small Wars, Big Data: The Information Revolution in Modern Conflict, we describe evidence on an approach that works (summarizing results from over 50 peer-reviewed publications fully or partially Minerva supported). To win locally, an allied government provides services to the population which make it worthwhile for some small number of people to share information with government forces on insurgent activities. That government stages sufficient forces to act on those tips – while protecting its sources from retaliation, and minimizing collateral harm to other civilians. Such an approach has been implemented successfully by U.S. forces and allies repeatedly, including in many parts of South Vietnam in the late 1960s and early 1970s, in large areas of the Philippines from 2005 onwards, in most of Iraq from mid-2006 through 2009, and in many parts of Afghanistan in 2010–12.

That recipe works locally with limited foreign presence, and at a modest cost to foreign governments, because the forces required are modest, and the necessary service provision by the government must merely exceed the value of that provided by rebels.

Winning the village, however, does not imply winning the war. And even winning almost all the villages can be insufficient, as the searing experience of Iraq’s return to violence in 2014-17 shows (not to mention trends in the Afghan civil war from 2014 on). Our local allies often lack the resources or will to control all of their territory, particularly if doing so requires confronting a powerful neighbor, an entrenched smuggling network in peripheral parts of their country, or taking significant domestic political risks. So, even if we have helped an allied country overcome an insurgency, they may lack the political will to forge a lasting peace.

Moving from local victories to a resolution of conflict takes a theory of change that goes beyond winning a succession of battles: we need a strategic vision for how to capitalize on winning villages, and for how to make the whole add up to a stable political settlement. The U.S. never formulated such a vision in Afghanistan. Perhaps now it should.

Managing Allies
One option in wars that are not easily won is to provide the local ally with the necessary resources to continue fighting with a small U.S. presence. We examine how this approach has worked across a range of cases in a forthcoming Minerva-supported volume Proxy Wars: Suppressing Violence through Local Agents. Our key finding is that successfully working through proxies to manage local security threats always includes incentivizing the ally to suppress the threat to U.S. national security interests. That approach has been successful when the senior power (generally the U.S.) considers how an ally’s interests differ from our own, and is willing to incentivize compliance. This may be the best option in conflicts that endure for decades.

For instance, in South Korea in the early 1950s President Rhee diverted US security force assistance from its intended aim of building security to instead staff a patronage-based officer corps. That effort continued even during the Korean War, once the front lines stabilized in January 1951. It was only in late-1951, incentivized by Truman’s threat of withdrawing U.S. support for growing the Republic of Korea forces, that Rhee professionalized his forces (he had resisted doing so in early-1951 despite clear evidence of North Korea’s capacity to invade). The book reviews eight other examples of local allies who renege on commitments when unincentivized.

Patient, Limited Intervention Can Create Space for a Political Settlement
Northern Ireland provides an example of a subnational conflict that appeared interminable, but was eventually resolved. In retrospect, the limited presence of British forces seems to have been a better choice than withdrawal. That case bears some similarity to modern small wars, including elements of rural insurgency as well as terrorism. The British government managed to suppress the violent threat sufficiently to negotiate a ceasefire and eventually a peace settlement with the Irish Republican Army (IRA), without investing the resources that would have been required to fully suppress Nationalist activity.

Similarly, in Colombia between 2002 and 2016, government forces supported by the U.S. were able to win village after village from the Revolutionary Armed Forces of Columbia (FARC), to the point that, by the 2016 referendum, millions of Colombians voted for a peace deal that would have been unthinkable a decade earlier. Voters did so in large part because they no longer felt threatened by the FARC’s violent tactics.

Back to Afghanistan
For too long there has been a gap in the discourse around how to deal with ‘small wars’ – a blank space awaiting a realistic approach to ending conflict in a world where victory of the type achieved in WWII is no longer a realistic option. The fact that a clear victory is unobtainable does not mean the answer is to do nothing. Neither does the fact that powerful states can do something mean that they always must engage.

Instead, our research indicates that one should first ask whether winning local fights—that the United States can help our allies do at modest cost—would also set them on the path to an eventual political settlement? We will rarely be able to help them win all the local fights, but we can almost always help win some. Our research thus suggests that before intervention, the U.S. and its allies should define success and assess whether a path to achieving that success runs through local victories

Returning to Afghanistan, we can now ask a tightly focused question: Is there an internal governance bargain that the Afghan government and the Taliban can agree to which all parties would prefer over the status quo of protracted conflict and which the neighbors—principally Pakistan—would comply with? If so, there is almost surely a cost-effective intervention through which the U.S. can help our Afghan ally put itself in a position to achieve that agreement. This may require a long-term commitment to military assistance combined with civilian development aid—both to keep our ally stable, and to monitor and incentivize the ally’s compliance with reduction threats to U.S. interests. Given what we now know about cost-effective approaches to fighting asymmetric conflicts, that long term investment may be small (certainly vastly lower than the costs of helping the state impose order over 100 percent of its mountainous territory), especially when compared to the return in terms of U.S. interests: achieving regional stability and countering international terrorism.

*The views represented here are those of the authors and do not reflect the views of any of the organizations that have funded the work referenced here, or of our co-authors on various projects.

Associated Reading
Berman, Eli, and David A. Lake, eds. 2019. Proxy Wars: Suppressing Violence through Local Agents. Ithaca: Cornell University Press.

Berman, Eli, Joseph H. Felter, and Jacob N. Shapiro. 2018. Small Wars, Big Data: The Information Revolution in Modern Conflict. Princeton: Princeton University Press.

Pickering, Jeffrey, and Emizet F. Kisangani. 2009. The International Military Intervention Dataset: An Updated Resource for Conflict Scholars. Journal of Peace Research. 46(4): 589–599.

Special Inspector General for Afghanistan Reconstruction (SIGAR). 2018. Quarterly Report to the United States Congress. October 30. Available at:



Eli Berman is Professor of Economics at University of California, San Diego a Research Director at the UC Institute on Conflict and Cooperation. He is the author of Radical, Religious and Violent: The New Economics of Terrorism, coauthor of Small Wars, Big Data: The Information Revolution in Modern Conflict, and coeditor of Proxy Wars: Suppressing Violence through Local Agents.
Jacob N. Shapiro is Professor of Politics and International Relations at Princeton University and directs the Empirical Studies of Conflict Project, a multi-university consortium that compiles and analyzes micro-level conflict data and other information on politically motivated violence in countries around the world. He is the author of The Terrorist’s Dilemma: Managing Violent Covert Actions and coauthor of Small Wars, Big Data: The Information Revolution in Modern Conflict.

Associated Minerva Projects
Deterrence with Proxies and Terrorism, Governance, and Development

Supporting Service Agencies
Office of Naval Research and Air Force Office of Scientific Research

Nota Bene
Content appearing from Minerva-funded researchers—be it the sharing of their scientific findings or the Owl in the Olive Tree blogs posts—does not constitute Department of Defense policy or endorsement by the Department of Defense.