In later papers, we expanded our analysis to include the extension of mobile networks in an area. This allowed us to examine the question of how mobile communications impact violence: do they allow insurgents to organize and increase violence, or do they allow civilian informants to communicate tips to government, thus decreasing violence? It turns out that in the asymmetric conflict in Iraq, expanding cell phone coverage did reduce violence. Importantly, our findings suggest that the mere threat of information sharing by noncombatants can reduce violence.

Other research, using a variety of different methodologies, supports our model and adds nuance to our findings. In a 2012 study, we used surveys in Pakistan to show that, contrary to popular conception, the poor are more likely to disapprove of insurgents because they are more likely to suffer from insurgent violence. Furthermore, in a 2014 paper, we used large-scale experiments to show that the mere perception of poverty and violence can change civilian support for insurgents.

In summary, smaller, smarter aid packages can reduce violence. So can the threat of information-sharing. Shifts in civilians’ perceptions of violence, and poverty can alter their support for militant groups, with potential implications for information sharing. All of this points to the fact that, in asymmetric conflicts, small-scale and often low-cost interventions can yield big results – information control being the key.

Multiple wars against a single enemy

So, is the current fight against Islamic State symmetric or asymmetric? The answer is “both.” The involvement of the United States in aiding the Iraqi government and Kurdish forces is spurring the evolution of the conflict in an asymmetric direction. If the war continues along this trajectory, then it will be crucial for the Iraqi government and its allies to make political accommodations with communities to increase the flow of information. Additionally, aid packages should be low-profile, informed by development experts and conditional on communities cooperating with the government. Iraqi forces should follow the model of community interaction exemplified by the “surge” of 2007, and the Iraqi government needs to find a way of convincing skeptical Sunnis that they have a future in the country, as the United States convinced Sunni tribal leaders in 2006 and 2007.

In Syria, by contrast, the atrocities of the Assad regime have precluded the kinds of international intervention and support to the government that would in turn allow it to fight a predominantly asymmetric conflict. Thus, while the Assad regime has fought its multiple enemies to an asymmetric stalemate -- none of them can overcome Assad’s army -- a symmetric conflict is unfolding between the Islamic State and the Free Syrian Army (FSA). This conflict features a familiar volleying for power along front lines. We know how to provide support in such a conflict: firepower – which can be provided from the air – is critical; information from non-combatants, less so, though it is still obviously useful.

The picture in Syria becomes more complex, however, when we consider the FSA’s struggle against a dominant government army, especially in cities. Our model provides us with recommendations for the kind of war the disadvantaged side should wage in an asymmetric conflict. It should apply as much violence as the public will tolerate. This is a thorny proposition, given the catastrophic results of the deterioration of the Syrian state. It is important to recall the end result of United States' support for Afghan rebels in its asymmetric war against the Soviet Union.

Identifying the areas where the fight is symmetric or asymmetric is important not only for strategy, but also for resource allocation. Applying data from past conflicts to our model reveals the margins where small expenditures in aid and information-gathering can achieve big results. Our results suggest that taking a blanket approach will be counterproductive. Instead, we should think of fighting different types of wars in different areas areas of conflict. The more asymmetric a war gets, the more important the flow of information becomes.

Commitment and shades on the map

In subnational wars, it is critical to understand not only the nature of the conflict but also the level of the local ally’s commitment. The hard truth is that our allies are sometimes unwilling to pay the price of exercising complete control over their territory. The black lines on our world map give a false impression of  territorial solidity. Not only are the majority of the world’s nations involved in one or another kind of border dispute – approximately 70 percent of the countries with significant military forces – many contain areas that their governments do not control. This is true, for example, of the Federally Administered Tribal Areas (FATA) which the Pakistani government has long given over to local tribes. It is also true of large chunks of Yemen with its patchwork government, and even pockets of Central and South American nations effectively ceded to drug cartels. Governments do not exercise control over these areas from lack of capacity or lack of will – the financial or political returns of exerting control over marginal territory is often low, even when these territories cause real problems for the rest of the world.

Therefore, we must ask the question of whether in a subnational conflict, the government is bringing all available resources to bear in order to win, or whether it simply does not feel an area is worth fighting for. This adds a further level of nuance to our predictions regarding asymmetric warfare. Perhaps the local ally is willing to conduct incursions, but not to provide sufficient governance to ensure a flow of tactically critical information from civilians. In Iraq, we have observed that the government does not try that hard to assert control over certain areas; it ceded much of the Sunni areas of Iraq very quickly to the Islamic State despite a superiority in numbers and military technology. The United States assisted Iraq in waging a successful asymmetric war to gain control over the western province of Anbar in 2007, only to later find that the Iraqi government lacked the will to govern that area. Anbar is now an Islamic State stronghold.

Therefore, in order to wage an effective war against the Islamic State, the United States should sit down with allies active in Iraq and Syria and identify territory that matters enough for them to commit troops to and eventually govern. Such a conflict will not feature actors controlling blocks of territory but chains of outposts, and will be characterized by various levels of symmetry and asymmetry. However, there will be areas, especially in Syria, that neither the Assad government nor the FSA will want to contest, and there is little we can do about that.

That brings us to the difficult issue of ungoverned spaces, which are uncontested by any state or subnational ally. Neither a symmetric or asymmetric war can be waged effectively in an uncontested area. These areas are especially dangerous because they could incubate the greatest terrorist threats, dangerous to Paris as well as Baghdad.

The United States has two constructive options to deal with such spaces. First, we can give allies reasons to police them, through incentives, through development programs that make them attractive, or through occasionally helping nudge noncompliant leaders such as Prime Minister Maliki towards the exit. Doing so is quite challenging, as Pakistan’s case demonstrates. Failing this strategy, a second option is to directly suppress the terrorist threat. The United States has strategies for this kind of warfare – developed in Pakistan and Afghanistan. They involve the unilateral employment of drones, special forces, and signal intelligence. A similar strategy may be unavoidable in some areas of Syria.

The commitment of allies is also important. The United States will remain dependent on how well its European allies, for example, control the radicalization of their Muslim populations.

The bottom line is this: we have long recognized that effective counterterrorism requires the cooperation of countries who are willing to governing all their citizens and territory. We must also recognize the limitations of working through countries and allies with more opaque and limited objectives, such as Iraq, the FSA and the Peshmerga.

Failing to recognize the type of war one is in can lead to massive waste and unrealistic expectations, as can failing to accurately diagnose the reasons for ungoverned space. The war against the Islamic State is not an old school war involving states contesting territory. Instead, the United States is fighting several very different wars against the same enemy: symmetric, asymmetric and a mix of the two as part of its efforts to combat terrorist threats. The first steps toward victory may involve creating a detailed, dynamic subnational map of which war is going on where, setting feasible expectations, and organizing our allies appropriately to deal with different types of conflicts in different ways using appropriate evidence-based strategies.

Eli Berman is a research director at the University of California Institute on Global Conflict and Cooperation and professor of economics at the University of California, San Diego.