1. Top of page
  2. Abstract
  3. Civil War as a Conceptual Variable
  4. When Does a Civil War Really Begin or End?
  5. Civil War and Violence
  6. Systemic Causes of Civil War
  7. Are Civil Wars Fundamentally Different from Interstate Wars?
  8. A Closing Word on Methodology
  9. Conclusion
  10. References

Florea, Adrian. (2012) Where Do We Go from Here? Conceptual, Theoretical, and Methodological Gaps in the Large-N Civil War Research Program. International Studies Review, doi: 10.1111/j.1468-2486.2012.01102.x

Since the early 1990s, the large-N civil war research program has been a vibrant one but has reached an analytical plateau because methodological issues have obscured fundamental conceptual and theoretical concerns. The existing ground-clearing work has shed light on macro- and micro-level determinants of internal conflict onset, duration, and termination, but has left the field theoretically impoverished. This article discusses remaining gaps in the quantitative civil war literature, and proposes conceptual, theoretical, and methodological remedies. Five main lacunae are identified. First, civil war may be a longer process, with several waves of escalation and de-escalation, than generally described in the extant literature. Second, existing theories conflate civil conflict with violence—war onset and violence may be conceptually distinct. Third, we have few systemic-level theories of civil war onset and duration. Fourth, we need better theories that allow us to determine whether civil wars are different from other types of wars. Finally, we need to go beyond state-centric monadic approaches, and be more rigorous when building our models for explaining civil war onset, duration, or termination.

Warfare has shifted away from great powers, away from conflict to civil war, insurgency, and terrorism. (Levy 2007:19)

The decline of interstate conflict in the post–World War II period and the end of the Cold War ushered in a paradigm shift in the study of war with students of conflict gradually turning their analytical gaze away from international conflict and toward civil wars. According to Kalyvas (2007), scholars’ renewed interest in the underdeveloped and under-theorized field of civil war in the early 1990s was premised on three main factors: first, World Bank experts specializing in the economies of the war-torn African states began to investigate the economic causes of civil conflict; second, with the virtual disappearance of interstate wars, many International Relations (IR) scholars turned to the study of internal conflict; and, third, the resurgence of ethnic conflict after the break-up of the Soviet Union and Yugoslavia led analysts to focus on various forms of violence exhibited in internal war. Since the early 1990s, the civil war field has been a vibrant one—theories, hypotheses, and mechanisms have been proposed and tested regarding internal conflict onset, duration, escalation, diffusion, or termination. In the early 2000s, the research program became dominated by large-N studies that shed light on socioeconomic and political correlates of civil war onset, duration, and termination, but that suffered from at least two limitations: (i) they were primarily state-centric in that they focused on state characteristics and ignored the strategic interactions between actors or the microdynamics of violence; and (ii) they over-privileged domestic variables over subnational and international ones.

My goal in this article is not to offer a comprehensive review of the findings in the vast civil war literature2; nor is it to pinpoint past or current theoretical and methodological advances in the field. Rather, I attempt to take the pulse of the large-N civil war research program, and identify remaining conceptual, theoretical, and methodological gaps that have prevented us from having a fuller understanding of civil war as a process composed of waves of escalation and de-escalation of violence rather than a series of one-shot independent events. The argument that I advance herein is that, despite the impressive methodological ground-clearing work3 of the late 1990s and 2000s, the quantitative literature on civil war still suffers conceptually, theoretically, and methodologically. As it will become clearer in the discussion below, my criticism of the large-N literature on civil wars is not epistemological, but theoretical and methodological. In other words, my goal is not to pinpoint the limitations of the quantitative method in general, but of the application of the method in the civil war research program.

This article proceeds as follows. The first section considers two conceptual problems that emanate from the casualty-threshold approach (the use of a specific number of battle-related deaths per year) for determining civil war onset, duration, and termination in the large-N literature. I argue that the casualty-threshold approach yields two inter-related problems: arbitrary and questionable codings of starting and ending dates for civil wars, and a conflation of civil conflict with violence. Better conceptualization is needed: on the one hand, civil wars may be longer processes, with several waves of escalation and de-escalation, than generally described in the extant literature; on the other hand, war onset and violence may be conceptually distinct. The second section looks at the few systemic-level explanations of civil war onset and duration and pinpoints their limitations. The third section focuses on the more recent debates of whether inter- and intrastate conflicts are comparable phenomena. The fourth section discusses methodological problems regarding the appropriate unit of analysis; corrections for temporal and spatial dependence; models for capturing multilevel causality; and models for accounting for multiple civil war outcomes. Finally, the fifth section draws the conclusions.

Civil War as a Conceptual Variable

  1. Top of page
  2. Abstract
  3. Civil War as a Conceptual Variable
  4. When Does a Civil War Really Begin or End?
  5. Civil War and Violence
  6. Systemic Causes of Civil War
  7. Are Civil Wars Fundamentally Different from Interstate Wars?
  8. A Closing Word on Methodology
  9. Conclusion
  10. References

The difficulty of characterizing civil wars is a conceptual problem rather than one of measurement. (Kalyvas 2003:476)

How do we know a civil war when we see one? At first sight, the concept may seem fairly unambiguous. A civil war is generally construed as a conflict: (i) confined within the territorial boundaries of a sovereign state; (ii) where the government is a full participant; (iii) violence is sustained and reciprocated; and (iv) a certain death threshold is reached (yearly and throughout the duration of the entire conflict).4 Upon closer scrutiny and against the empirical evidence, it soon becomes obvious that each of these arbitrary definitional criteria is questionable at best.

First, there is little theoretical rationale for imposing on the concept the internality of war to the territory of a single sovereign state. While most internal conflicts may indeed originate within the boundaries of a single country, many civil wars actually become transnational in character5 (for example, the Bosnian civil war of the early 1990s). So, by restricting the conceptual domain to a sovereign state’s boundaries, we are implicitly saying that civil war as a process (that is, with all its phases—escalation, de-escalation, diffusion, termination) is unequivocally an intra-national phenomenon—a statement that any astute observer from within or outside the academia would certainly frown at. Second, there does not seem to be any overwhelming rationale for limiting civil wars to confrontations between the government and one or more claim-making collective actor(s).6 In some civil war situations, the government may actually not be a combatant: actors fighting each other in countries that lack structures of governance (for example, Somalia) or in countries where the government is yet another player (for example, Eritrean People’s Liberation Front-EPLF vs. Eritrean Liberation Front-ELF in the 1970s) could be as consequential to civil war outcomes as the government–collective actor interaction.

Third, if violence is indeed the central discriminating factor, then we need to be more specific about what level of violence is needed to observe a civil war rather than a different form of conflict. Fourth, if we rely on the death threshold to characterize civil war onset, we may be actually conflating violence with conflict and may thus be ignoring the ample empirical evidence which points to the endogeneity of violence to war.7

Coming up with a conceptual and operational definition of civil wars is a difficult, but not intractable, endeavor. Scholars have tended to treat civil war as a largely self-evident concept and have assumed unit homogeneity for the cases included in the large number of available data sets on internal conflict.8 Not only is there a tendency to assume that everyone knows what a civil war is, but many researchers believe “that available data on conflict will accurately reflect the theoretical concepts” (Gleditsch 2002:73). In many ways, and against Sartori’s (1970) warning more than 40 years ago, data collection has continued unabated despite the lack of proper conceptualization. Not only we don’t clearly know what civil wars are, but we also cannot really tell what civil wars are not.9 As a result, without theoretically driven conceptualization, civil war may not mean the same thing to all scholars at all times. The consequences of this state of affairs are quite serious for our theory-building and hypothesis-testing enterprises. It would not be a gross exaggeration to state that a conceptual morass has engulfed the field whereby concepts remain abstract and highly aggregated; conceptualization of civil conflict has been insufficiently integrated with empirical research; conceptual fuzziness has led to potential incomparability of cases in large-N research; and civil war as a variable is not quite pitched at the right level so as to connect both upwards (toward theory) and downwards (toward empirical data).

Because of improper conceptualization, the gap between concepts and data is getting wider. Existing data are still treated “with excessive reverence as if the pristine raw data were a fully unbiased and accurate arbiter of the analytical value of our theories” (Gleditsch 2002:197). An unambiguous conceptual definition significantly limits any schism that may exist between theory and data. Moreover, how we define our concepts has implications for how we select the key elements of the civil war contexts—careful conceptualization ensures that these contexts are analytically equivalent.10 Taking the civil war concept for granted is dangerous because we have no real sense of where the conceptual boundaries lie. Thus, we are left with a familiar label for some form of conflict and little understanding about its dynamics.

To be fair, it’s not easy to come up with a “perfect” conceptual definition and operationalization of civil war.11 We are dealing here with a macro-level concept that cannot easily be factored down into specific, micro-level representations.12 At first blush, the conceptualization and operationalization problems may seem unavoidable. I disagree. While it may be difficult to come up with the “perfect” definition of civil war that exhaustively captures all phenomena that can be classified under the civil war rubric, we can nevertheless set unambiguous boundaries that determine the appropriateness of our indicators. At least two interlinked aspects need to be addressed in order to come up with a better specification of civil war’s conceptual boundaries: (i) when exactly a civil war begins and ends and (ii) whether civil war and violence are theoretically equivalent. I now turn to a discussion of each of them.

When Does a Civil War Really Begin or End?

  1. Top of page
  2. Abstract
  3. Civil War as a Conceptual Variable
  4. When Does a Civil War Really Begin or End?
  5. Civil War and Violence
  6. Systemic Causes of Civil War
  7. Are Civil Wars Fundamentally Different from Interstate Wars?
  8. A Closing Word on Methodology
  9. Conclusion
  10. References

Contemporary civil wars tend to have an intermittent quality, dying down for some years before coming to life again. Conflicts may simmer for years at low intensity, then erupt or re-erupt into full-scale civil war. (Hironaka 2005:150)

Too many cases are sufficiently ambiguous to make coding the start and end of the [civil] war problematic and to question the strict categorization of an event of political violence as a civil war as opposed to an act of terrorism, a coup, genocide, organized crime, or international war. (Sambanis 2004:815)

Current scholarship embraces a casualty-threshold approach to determine civil war onset, duration, and termination.13 For example, the PRIO/UPPSALA data set requires a minimum of 25 battle-related deaths to code for the onset and duration of civil wars.14 I argue that, while existing coding rules may facilitate quantification, they actually create confusion about a civil war’s duration. If we look closer at the empirical evidence and regard civil wars as processes rather than one-shot independent events, then internal wars’ start and end dates are not trivial.15 These problems are not limited to the study of civil wars. For example, the rivalry research program is more or less confronted with similar issues. On the one hand, the “conflict-density approach” (Diehl and Goertz 2000; Klein, Goertz, and Diehl 2006) identifies rivalries by looking at a specific number of militarized interstate disputes (MIDs) for dyadic pairs within specific time periods.16 On the other hand, the “subjective approach” (Thompson 2001; Colaresi, Rasler, and Thompson 2008) focuses on decision makers’ perceptions about the existence of competitive and threatening enemies. Both are imperfect: the former excludes cases that do not register a sufficient number of MIDs and is circular in the sense that it uses a conflict record to explain a conflict record; the latter cannot identify with exact precision the start or duration of rivalries since it is based on subjective beliefs of enmity.17

Much as is the case with interstate rivalries,18 it may be more useful to think of civil wars as longer processes involving escalation and de-escalation rather than onset, termination, and reoccurrence. Civil wars are not just isolated, one-shot events but peaks in more continuous chains of interaction (Gleditsch 2002:85). Put differently, single disputes may be part of a broader escalation–de-escalation pattern rather than independent events. Thus, without clear-cut observable outcomes—such as enforceable peace agreements, complete military victory from one side, unambiguous institutional outcomes (for example, secession, autonomy)—we cannot say (and code accordingly) that a civil war has really ended.19 What is currently coded as several civil conflict onsets can actually represent mere variation along the escalation–de-escalation continuum within the same conflict.

To illustrate the plausibility of this alternative conceptualization, let’s take a time series view of a country X exhibiting several episodes of violence along a certain timespan.20 Implicitly, we are assuming that violent events are not independent of one another. Thus, to accurately explain the extent of violence at time t in country X, we cannot ignore the effects of a prior violent episode at time t-1. To facilitate comprehension, a simple first-order autoregressive (AR1) equation will suffice to illustrate the dynamic interaction between current and past episodes of violence in country X. Hence, we have

  • image(1)

where yt is the level of violence at time t, ϕ is a parameter of the model, and εt is a white noise component with zero mean and constant variance. More generally,

  • image(2)


  • image(3)

This simple first-order autoregressive equation approximates many political phenomena whereby the effect of a past event persists immediately after its occurrence but exponentially diminishes over time. Consider the situation of a sudden drop in economic growth due to an exogenous shock such as a global economic recession, for instance. Its greatest impact is likely to be felt immediately after it occurs, but its effects are expected to vanish exponentially with each period t. For the equation above to capture the idea of exponentially diminishing impact, the parameter ϕ must be restricted within the bounds of stationarity: −1 < ϕ < 1. If ϕ = 1, then we are simply stating that the impact of past events does not diminish over time but remains constant. If ϕ > 1, an escalatory or growth process is implied—that is, as time goes by the impact of a past event is actually greater.21

What does this have to do with civil wars? The main point that I want to emphasize with the aid of this simple example is that, while most events do exhibit an exponentially decaying function, it may be the case that at least a subclass of civil wars does not follow this pattern and displays an escalatory function. Hence, under certain conditions—such as the lack of a clear victory from one side, or a clear-cut institutional outcome—each additional period of peace after the violence episode at time t-1 may actually increase the probability of violence at time t.22 In other words, it would not be totally unreasonable to state that, at least in some cases, peace times between episodes of violence could actually capture a “boiling container effect” of past events23 whereby with each peaceful time point the likelihood of recurrent violence is higher.24

Current codings artificially slice civil wars and fail to capture the heterogeneity of peace years between civil war onsets. Not all peace years are similar concerning the effect of actor interactions during any peace year on the posterior probability of war. In other words, contrary to the assumption underlying current coding practices, various peace years do not have similar effects on the likelihood of war recurrence: peace years that capture a lull in hostilities or a military stalemate may have a different impact than peace years after a peace agreement or military victory. As Galtung (1969) argued a while ago, peace is an aggregate concept: it may connote both the absence of conflict between antagonists—negative peace—and cooperation and trust between former opponents—positive peace. Most of the conflict literature—inter- or intrastate—conflates negative peace with positive peace.25 This unfortunate, but persistent, conflation leads to omitted variable bias (King 2001) as the variation in the level of latent hostility during peace years remains unmeasured.26 Rarely are peaceful years—within the same conflict or across conflicts—analytically equivalent. Therefore, negative peace years in civil war situations—that is, peace years following the cessation of hostilities without a clear victory from one side, credible peace agreement, or mutually agreed outcome—may actually increase the likelihood of war. If we unpack the heterogeneity within peace years, we may observe fewer civil war onsets and terminations, and longer civil war durations with larger fluctuations in violence from one episode to another.

The heterogeneity in peace years has important methodological implications: it suggests that we are, in fact, dealing with two populations of cases—positive peace cases or those cases where civil war recurrence is unlikely because the civil war has really ended; and negative peace cases that merely capture a lull in hostilities rather than termination. A duration analysis of civil war implies that, if given enough time, all observations will fail—that peace years observations will eventually terminate and we will observe conflict recurrence.27 This is premised on the assumption that, ceteris paribus, all peace years observations exert similar effects on conflict reoccurrence. If negative peace is fundamentally different from positive peace in affecting the likelihood of conflict, we then have different risks of conflict and different populations of cases: one population composed of immune cases or those cases of positive peace that will never experience civil war and one population of exposed cases or those cases of negative peace that are likely to experience renewed violence. In this case, a split-population estimator, which takes into account the two types of populations, would be more appropriate than traditional estimators.28

To briefly illustrate the plausibility of this alternative conceptualization and operationalization, consider two examples of civil war processes within a relatively short timespan: violence in Zaire (DRC) from the 1960s to the 1970s and in Sri Lanka from the 1980s to the 2000s. In the case of Zaire,29 the PRIO/UPPSALA data set codes three civil war onsets for the 1964–1978 period (1964, 1967, 1977), while in the case of Sri Lanka,30 the same data set also codes three civil war onsets for the 1984–2008 period (1984, 2003, 2005). A feasible alternative would be to code for a single civil war in each case: in Zaire (DRC) lasting from 1964 to 197831 and in Sri Lanka unfolding from 1984 to 2009.32 To elaborate on the Sri Lankan case, what are currently coded as civil war terminations in 2003 and 2005 are in fact mere interregna between violent episodes within the same conflict. Following a Norwegian-mediated ceasefire (thus, not a comprehensive peace agreement which would have been an indubitable indicator of conflict termination) in 2002, the Liberation Tigers of Tamil Eelam (LTTE) withdrew to safe havens within Tamil Eelam to regroup and prepare its escalatory attacks in 2003. The conflict de-escalated again in 2004 when the island was struck by a powerful tsunami which forced both sides to concentrate on socioeconomic rather than military activities. In 2005, the conflict escalated when the Sri Lankan foreign minister was killed in a rebel attack. Finally, in 2009 the conflict terminated with the military defeat of LTTE. The Sri Lankan example illustrates a simple, but largely overlooked, fact: because a conflict does not register the minimum casualty threshold in a given year, it does not necessarily mean that it has truly ended. Dyads which have experienced several civil wars within a short timespan are particularly susceptible to too much arbitrariness in coding rules. What is currently seen and coded as the end of a civil war may actually represent a mere interlude between episodes of violence within the same conflict. As Hironaka (2005:151–2) puts it,

The “end” of a civil war might merely mean that the insurgents were pushed into hills, mountains, or rural areas without actually surrendering…If the opposition can neither be fully destroyed nor fully placated, how can [civil] wars truly end? A number of countries experience perpetual low-intensity conflict. In some years, perhaps owing to a temporary military stalemate or a fragile cease-fire, casualties may be low enough to consider a war to be over. When fighting returns, we may say that war has recurred. But it might be more accurate to say that such wars never really ended.33

Civil War and Violence

  1. Top of page
  2. Abstract
  3. Civil War as a Conceptual Variable
  4. When Does a Civil War Really Begin or End?
  5. Civil War and Violence
  6. Systemic Causes of Civil War
  7. Are Civil Wars Fundamentally Different from Interstate Wars?
  8. A Closing Word on Methodology
  9. Conclusion
  10. References

[V]iolence is employed by both those who wish to upend an existing order and by those who want to sustain it. (Kalyvas, Shapiro, and Masoud 2008:1)

A second problem underlying the casualty-threshold approach to internal war onset, duration, and termination is the fusing of conflict with violence. Civil war research treats violence as a starting point, “either examining the presence of violence compared to its absence, or comparing degrees of violent behavior once a conflict already exists” (Chenoweth and Stephan 2010:250). In other words, civil war processes (onset, duration, termination) are conflated with violence.34 At first sight, this may look undisputable—after all, a bloody phenomenon such as civil war cannot be fully captured by a bloodless referent. I submit that there are at least two reasons why this conflation may be problematic for arriving at a more fine-tuned understanding of internal conflict dynamics.

First, recent work (Kalyvas 2006; Weinstein 2007) on the microdynamics of violence provides ample evidence that points to the endogeneity of violence to conflict. If violence is typically endogenous to various civil war processes, then it may be the case that a civil war actually starts (for example, with war declarations, casualty-free military skirmishes, or de facto territorial control) before violence ensues. I suggest that we need to distinguish civil war from violence beyond current directions. For example, Kalyvas (2006, 2010) argues that only through disaggregation can we fully account for the endogeneity of violence to conflict by focusing, for instance, on private motives (for example, eliminating a rival; personal revenge) for violence that have little or nothing to do with the macro-dynamics of conflict. In fact, disaggregation (of violence, space, actors, and levels of analysis) lies at the core of the recent turn in the civil war literature (Kalyvas 2006; Weinstein 2007; Kalyvas et al. 2008; Chenoweth and Lawrence 2010) away from focusing on recurring conditions that increase the likelihood of internal conflict and toward micro-level dynamics. This theoretical and analytical shift yields clear payoffs: the richness of case study detail is no longer sacrificed in favor of sweeping generalizations generated from quantitative investigations; theory and data are more closely matched; we have a better grasp of both agency (actor preferences and behavior) and contingency (subnational and national environmental conditions conducive to violence). While the disaggregation approach is definitely attractive, it nevertheless suffers from a key drawback: too much disaggregation ineluctably leads to a shift in explanandum—from civil war as a process which encompasses both violent and nonviolent forms of collective action,35 to simply the variation in the level of violence.36 Therefore, disaggregation is no panacea for the lingering problem of civil wars’ start and end dates.

I argue that, with more elastic indicators of conflict onset, such as war declarations, casualty-free military skirmishes, or de facto territorial control, disaggregation may not even be necessary. Critics may counter that indicator elasticity will blur the civil war concept beyond recognition. I contend that good theory can be fruitfully informative when coming up with good indicators of conflict onset. In interstate war research, a war declaration signals war onset even though violence is not coterminous with it. Similarly, a war declaration in civil conflicts (or any observable action equivalent to war declaration) can also signal war onset with violence succeeding it. Consider briefly, for the sake of exposition, internal conflicts over the so-called de facto states—state-like polities that lack international recognition (for example, Abkhazia; Nagorno-Karabakh; Republika Srpska; Somaliland; Transnistria; Turkish Republic of Northern Cyprus; Western Sahara). A cursory look at the historical evidence suggests that de facto control over a territory that belongs to a sovereign state usually predates the onset of hostilities between the titular government and the collective actor in control of the de facto state.37

Another objection to relying on more elastic indicators of civil war onset may be that events such as war declarations, casualty-free military skirmishes, or de facto territorial control are not at all common in internal conflicts. How else can we observe onset then? Can onset be visible independently of the level of violence? To address this conundrum requires that we look at civil wars as larger processes of contention where various forms of violent and nonviolent collective action co-evolve. A political contention perspective (Tilly 1978; Rule 1988; McAdam, Tarrow, and Tilly 2001; Tarrow 2011) strongly calls for a separation of “the determinants of collective action from the determinants of violent outcomes to collective action” (Tilly 1978:183). In other words, we need to distinguish between determinants of civil war onset and determinants of violence in civil war situations. If onset and violence are indeed etiologically distinct, the start date for a civil war needs to be theorized a priori rather than established a posteriori based on recorded levels of violence. When events such as war declarations, casualty-free military skirmishes, or de facto territorial control are not clearly observable, we can, alternatively, look for indicators of a contested sovereignty situation which signals the emergence of (a) collective actor(s) threatening the displacement of existing power holders (Spruyt 2005).

In many respects, a contested sovereignty situation is not unlike a multiple sovereignty situation that in the social movement literature (Gamson 1975; Tilly 1978; Rule 1988; Goldstone 2001; Goodwin 2001; Tarrow 2011) marks the onset of revolution. Multiple sovereignty in revolutions obtains when a “population find themselves confronted with strictly incompatible demands from the government and from an alternative body claiming control over the government—and obey the alternative body. They pay taxes to it, provide men for its armies, feed its functionaries, honor its symbols, give time to its service, yield other resources, despite the prohibition of the still-existing government that they formerly obeyed. Multiple sovereignty has begun” (Tilly 1975b:520–1). Thus, under multiple sovereignty, we observe fragmentation of state power (Tarrow 2011:210) such that no single legitimate authority dominates the entire government apparatus: “different elements of state power are controlled by various members of the polity (government and challengers)” (Rule 1988:178). Multiple sovereignty in revolutionary environments ceases to exist when a collective actor establishes control over the government (Tilly 1978:191).

If a contested sovereignty situation could indicate civil war onset, when would it obtain? We would recognize such a situation when a government, parts thereof, or a given territory under its jurisdiction becomes the object of mutually exclusive claims from one or more mobilized collective actors.38 Several indicators could point to such circumstances: displacement of a power holder by another; government’s loss of control over the army and other instruments of violence; a collective actor’s control over some portion of the government (for example, territory; functional subdivision); fragmentation of the polity into two or more mobilized collective actors, each claiming exclusive control of the government.39 Granted, this alternative method for determining civil war onset is quite labor-intensive as it forces the analyst to look harder at historical facts. Yet, the payoffs are well worth the effort—by examining processes in-depth, the investigator will end up having a better theoretical handle of the complexity of civil war, and the analytical gains will accrue exponentially with the unveiling of each episode in the conflict.

If violence is retained as the most reliable criterion by which we identify civil war onset, duration, and termination, we’ll end up stating that we have more or less of a civil war rather than saying that we have a civil war with more or less violence. In internal conflict, collective actors may resort to both violent and nonviolent forms of collective action40 (for example, assassinations, riots, strikes, demonstrations, looting, ethnic cleansing, politically motivated arrests, indiscriminate killing). Therefore, to paraphrase Clausewitz’s famous aphorism, violence is the mere continuation of collective action by other means—it is yet another “form of collective action, oriented to the same purposes that contending [actors] pursue in ‘normal’ conditions” (Rule 1988:175). Violence, as an extreme but “normal” process of collective action, is but an outgrowth of the strategic interaction among actors (Tilly 1978:183).

Second, if violence is indeed endogenous to war rather than a precondition thereof, then we need to be more rigorous about theorizing on the role of the participants in civil war—particularly the state—in perpetuating or limiting the extent of violence. Unfortunately, the causal role of the state—as an actor and as a set of institutions that enable or constrain behavior—remains under-theorized. Many cross-sectional accounts of civil war occurrence, duration, and termination focus on country-year structural characteristics that may facilitate the break-out or escalation of violence rather than on actors’ strategic interactions. By doing so, they are only able to conclude that civil war has a greater likelihood of “happening” in a given country-year. This is utterly unsatisfactory because we are left with an incomplete view of the dynamic interplay between the sides involved in the outbreak and perpetuation of violence. Any conflict—global, regional, intrastate, or otherwise—is fundamentally centered on dynamic actor behaviors rather than on static (or slow-moving) structural elements.41 As Fearon (1995) usefully reminded us a while ago, our understanding of war in general will remain incomplete without a theory of strategic interaction.42

Thus, to get a clearer picture of actors’ interplay in civil war—in effect, to fully comprehend the ebb and flow of violent episodes throughout the entire span of an internal conflict—a minimal set of assumptions about the state (strong, weak, non-present, full participant) is necessary from the very outset. For example, if we build our explanation for the variation in violence on a state weakness assumption, we are able to shed clearer light on the bottom-up processes that are conducive to violence in the sense that state weakness offers ample political space and structural opportunities for social actors to direct violence against the state or toward one another. Conversely, if we construct our accounts for the fluctuations in violence on a state strength assumption, we can better illuminate the top-down processes through which the state engineers or directs violence toward social actors.43 Furthermore, if we are more precise in our assumptions and envision a poorly institutionalized state, then our analytical framework for unveiling the variation in violence may focus exclusively on the strategic interactions that take place within the state apparatus. For example, Acemoglu, Ticchi, and Vindigni (2009) have argued that in poorly institutionalized states, the political moral hazard caused by a strong military is the main catalyst for the perpetuation of internal violence. Their argument is elegant in its simplicity:

[In poorly-institutionalized states], the checks that would prevent a strong military from intervening in domestic politics are absent. This makes the building of a strong army a double-edge sword for many civilian governments, even if such an army is necessary for defeating rebels and establishing the monopoly of violence over their territory…The civilian government-military interaction is complicated by the fact that the elite cannot credibly commit to not reforming and downsizing the military once the civil war is over. Consequently, a stronger military, which is necessary for defeating the rebels, may also attempt a coup. (Acemoglu et al. 2009:1)

If violence is indeed endogenous to conflict, then a promising starting point for analyzing the variation in violence would be to consider the nature of the state and its behavior as variable rather than fixed. It is high time we “brought the state back in” our theories of civil war: “changes in state behavior rather than particular classes of states, may better explain episodes of [v]iolence [in civil wars]…The state, rather than being absent and unable to serve as a security guarantor, is often an active participant in violence” (Chenoweth and Lawrence 2010:7,12).44

To conclude this section, how can we find our way out of the conceptual and theoretical morass that has engulfed the large-N civil war literature? One solution to the problems induced by the casualty-threshold approach would be to go back to the drawing board and recode the end date of civil wars based on clear-cut observable outcomes, such as enforceable peace agreements, complete military victory from one side, unambiguous institutional outcomes (secession, autonomy), rather than on arbitrary battle-related deaths. This is the hard road. Alternatively, a palliative solution to the problematic casualty-threshold approach would be to employ a split-population estimator that takes into account two populations of cases: one population composed of immune cases that will never experience civil war and one population of exposed cases that are likely to experience renewed violence. Finally, a substitute coding for the start date of a civil war is to focus on more elastic indicators of conflict onset (war declarations, casualty-free military skirmishes, de facto territorial control, contested sovereignty situation) which may indicate that conflict onset actually predates violence.

Systemic Causes of Civil War

  1. Top of page
  2. Abstract
  3. Civil War as a Conceptual Variable
  4. When Does a Civil War Really Begin or End?
  5. Civil War and Violence
  6. Systemic Causes of Civil War
  7. Are Civil Wars Fundamentally Different from Interstate Wars?
  8. A Closing Word on Methodology
  9. Conclusion
  10. References

It is inappropriate to treat civil war as a fully domestic phenomenon. (Gleditsch 2007:294)

I now turn to another insufficiently explored problematique in the civil war research program—systemic causes of internal conflict. The current civil war literature focuses chiefly on national-level attributes for unveiling the causes of internal conflict.45 This closed-polity approach whereby countries are treated in isolation is incomplete for having a clearer image of civil conflict.46 As Skocpol (1979:30) observed some time ago, the larger geopolitical environment “creates tasks and opportunities for states and places limits on their capacities to cope with either external or internal tasks or crises.”47 States are not isolated polities, but are embedded in both regional and international structures; therefore, we must pay closer attention to those regional and international processes that affect civil war onset or duration.

Existing research on the external dimensions of civil war overwhelmingly concentrates on two classes of effects: neighborhood and systemic effects. The first is by far the most popular. Scholars have proposed a myriad of mechanisms through which neighborhood affects the likelihood of conflict or alters civil war dynamics. For instance, we know that the transnational presence of ethnic kin increases the likelihood (Woodwell 2004; Cederman et al. 2010) and duration (Salehyan 2008) of civil war; civil wars tend to be spatially interdependent (Gleditsch 2007); refugee flows constitute a negative externality of internal conflict and increase the probability of violence by facilitating the transnational spread of arms, combatants, and ideologies and by altering existing ethnic compositions (Gleditsch and Salehyan 2006); diaspora in neighboring countries provide support for the rebellion, especially when fatalities are involved (Woodwell 2004); and regional rivalries enable access to external bases and contribute to longer duration of conflict (Salehyan 2008).

If the neighborhood or sub-systemic effects have so far received a great deal of attention, the systemic effects have been addressed less frequently. Truly systemic explanations are supposed to zoom out micro- and meso-level dynamics; that is, they should locate explanatory variables at a higher level of aggregation than the regional, the national, or the subnational. Such theories would privilege explanations at a higher level of abstraction than cross-border linkages, refugee flows, or support from external actors that are so prevalent in the “neighborhood effect” strand of the literature on the external dimensions of civil wars. Systemic frameworks would concentrate, for instance, on macro-level factors such as patterns of decolonization and state formation accompanying global wars, changes in international requirements for statehood that may encourage various forms of internal violence, or changes in the technology of warfare and rebellion associated with a global shock such as the end of the Cold War.

A few studies from without and within the field look rigorously at systemic drivers of internal conflict. One macro-level explanation for the prevalence of civil wars comes from Wimmer and Min (2006) who turn Tilly’s (1975a, 1985, 1990) war-making-state-making argument on its head, and posit that both inter- and intrastate conflicts are outcomes of similar state formation processes. In effect, Wimmer and Min suggest that it is state formation processes which induce a combustible co-evolution of both inter- and intrastate war rather than the other way around:

Both civil and inter-state wars are fought over the institutional structure of the state, and thus are most likely to break out when these institutional principles are contested… The mechanisms relating nation-state formation to war are similar: wars over territory inhabited by co-nationals on the other side of a state border (commonly called irredentist or revanchist wars) follow the same logic of nationalist politics that may drive civil wars, as majorities and ethnic minorities compete for control over the state. (Wimmer and Min 2006:869)

Another systemic account (at least for a subset of civil wars) comes from Hironaka (2005) who contends that the post–World War II refusal of the international community to countenance secession outside the decolonization process has encouraged the proliferation of civil wars by protecting weak states with artificial and contested borders from fragmenting. Kalyvas and Balcells (2010) propose a third macro-level explanation which suggests that the end of the Cold War has fundamentally altered the technology of rebellion and has led to the proliferation of long-lasting symmetric-unconventional internal wars. Finally, Rasler (1983) argues that it is misleading to characterize internal wars as having essentially domestic origins. Using the case studies of Lebanon in 1958 and 1975, she insists that external forces create the conditions for internal war. Both civil wars, she posits, were inspired by regional and international politics.

These macro-level studies of internal conflict do indeed offer plausible accounts for the prevalence of civil wars but share one major limitation: they leave underspecified the exact processes through which larger systemic forces affect the likelihood or duration of internal war. For instance, Kalyvas and Balcells’ argument about the effect of the Cold War on the technology of rebellion necessitates a proper specification of impact. Should we expect a step function whereby following the abrupt collapse of the bipolar system rebels are confronted with different but permanent incentive structures? Or should we anticipate a pulse function whereby the effect of the end of the Cold War is strongly felt in the proximate years but then diminishes with time? How much does it last before all actors adapt their strategies to new systemic conditions? More importantly, if both inter- and intrastate wars tend to co-evolve during state formation waves, as Wimmer and Min (2006) suggest, can we really differentiate between these two types of conflict? Are they analytically equivalent? I discuss that possibility in the next section.

Are Civil Wars Fundamentally Different from Interstate Wars?

  1. Top of page
  2. Abstract
  3. Civil War as a Conceptual Variable
  4. When Does a Civil War Really Begin or End?
  5. Civil War and Violence
  6. Systemic Causes of Civil War
  7. Are Civil Wars Fundamentally Different from Interstate Wars?
  8. A Closing Word on Methodology
  9. Conclusion
  10. References

General theories of conflict should be applicable to both civil and inter-state conflicts. (Cunningham, Gleditsch, and Salehyan 2009:595)

Might interstate and civil wars be caused by a similar constellation of factors? This is both a theoretical and empirical question. The conflict literature maintains a strict distinction between intra- and interstate wars that may not be as theoretically clear-cut as the terms suggest and that may not justify separate study. The type of unit involved in warfare is the standard discriminating feature that distinguishes interstate conflicts from intrastate conflicts where an interstate dyad contains two sovereign states and an intrastate dyad contains one or none. This categorization rests on two key assumptions: (i) that sovereignty is effective within sovereign states and (ii) that state behavior is fundamentally different from nonstate behavior. As a result of this dichotomization, there has initially been little collusion between the two types of literatures with interstate conflict researchers being skeptical about applying theories of international conflict to wars within countries. However, as the civil war research program became populated with IR scholars in the early 1990s, it soon became clear that “sovereignty is clearly less than fully effective within many existing states, and similar problems of enforcement and contracting under anarchy obtain within states as well” (Gleditsch 2002:75). As a consequence of the influx of IR students into the traditionally marginal field of civil wars, we learned that there are important similarities in bargaining and conflict processes between interstate and civil wars:48Posen (1993) pointed out that, under conditions of the breakdown of domestic order, an internal security dilemma is the principal catalyst for prolonged violence; Fearon (1995) and Walter (1997, 2002) argued that the same commitment problems found at the international level are present among internal conflict actors as well; Toft (2002, 2003, 2006) posited that just like sovereign states fail to reach agreements because some issues are indivisible,49 issue indivisibility also prevents civil war participants from striking long-lasting bargains.

So, if anarchic situations and bargaining issues affect state and nonstate actors in similar ways, what justification is there left for separate study? Why not test our theories on both types of conflict? Scholars’ reluctance to do so may be grounded in the realization that, despite a few similarities, there still remain important distinctions between inter- and intrastate wars.50 Civil wars are longer, more frequent, and more deadly than interstate wars (Regan 2002; Collier and Hoeffler 2004; Lacina 2006); are fought by actors with asymmetric capabilities (Arreguín-Toft 2005); exhibit more salient commitment problems that international wars due to the post-conflict environment where internal actors, unlike states, have to interact frequently (Fearon 2004); unfold differently from interstate conflicts with civilians being more likely to be disproportionately victimized (Kalyvas 2006); and display a wider range of outcomes than international wars (Chapman and Roeder 2007). However, upon closer inspection, it becomes obvious that the above distinctions pertain to how wars unfold and terminate (that is, to war processes) rather than to their underlying causes.

So, are we looking at the right set of denominators that allow us to differentiate between the two types of wars? I submit that the main reason for our difficulty in adjudicating between the competing views on the similarities/differences of interstate and civil wars has something to do with a unit type bias in conflict research. As long as the literature remains dominated by a focus on the sovereign state as the sole unit worthy of investigation, we’ll always find similarities and differences between the two types of wars and the debate will not be put to final rest.

Mainstream IR research privileges the nation-state as the unit of analysis. While existing works pay due attention to the variation in the behavior of states as standard units in international politics, the nature of these units is generally treated as a constant. Most of the literature is replete with approaches that take the institutional form of the modern state as given and exclude alternative polities from analysis. Thus, nonstate actors are often dismissed as mere anomalies to an international system dominated by officially recognized states. This is quite surprising given that “the nature of the units among which relations occur has important implications for the structure of international relations” (Herz 1957:473). Unit type matters at least as much as the distribution of capabilities among units. As Spruyt (1996:5–17) puts it, structure is at least partially determined by the prevalent type of unit. Hence, to fully understand the structure of the international system, we have to first explain the synchronic and diachronic variation in the type of units that exist in the system.

At any given point in history, there has been little systemic stasis in terms of the types of unit in the system—alternative units have constantly formed. A political map of pre-Westphalia Europe shows a plethora of independent or semi-independent principalities, duchies, and states-kingdoms. Post-Westphalia, the modern state coexisted with city-states, empires, and city-leagues. Even in the post–World War II geopolitical landscape, nonstate actors have been a constant feature of a world dominated by recognized sovereign states. From this perspective, systems are rarely stagnant or stable. This shows that, when it comes to unit type, the international system is much more kinetic than mainstream IR theories portray it (Fazal 2007:40).51

One solution to the debate over the interstate–intrastate war dichotomy is to allow for variation in the type of units operating in international politics. This way we can better address the question of whether the interstate–intrastate conflict distinction is theoretically justifiable. This approach would entail shifting our analysis from a legalistic logic to a territorial logic—that is, from internationally recognized sovereign states and unrecognized nonstate actors to geographic entities that exert de facto control over a given space (regardless of their “official” status) for varying amounts of time.52 A territorial logic would enable us to shed clearer light, for instance, on those conflicts between a sovereign state and a de facto state (for example Georgia vs. Abkhazia) that are traditionally categorized as civil wars but that look very much like conventional interstate wars. This approach would also require redefining war in a more encompassing way. Because it is devoid of any unit type bias, Levy and Thompson’s (2011) suggestion may be a promising start in that direction: war, in general, can be simply understood as sustained, coordinated violence between political organizations. Hence, to resolve the lingering debate over the interstate–intrastate war dichotomy, we need stronger theoretical foundations, not data.

A Closing Word on Methodology

  1. Top of page
  2. Abstract
  3. Civil War as a Conceptual Variable
  4. When Does a Civil War Really Begin or End?
  5. Civil War and Violence
  6. Systemic Causes of Civil War
  7. Are Civil Wars Fundamentally Different from Interstate Wars?
  8. A Closing Word on Methodology
  9. Conclusion
  10. References

No single factor and no single level of analysis provides a complete explanation for the causes of war. As a result, theories of war must necessarily combine causal variables from different levels of analysis. (Levy 2007:22)

With a few exceptions,53 quantitative studies of civil war focus on the country-year as the main unit of analysis. The modal strategy is to take an off-the-shelf data set on civil wars for a given time period (usually, 1945–2008) and construct logit or probit models to probe whether certain country-level structural covariates (for example, regime type; level of development; resource endowments) affect the likelihood of civil war onset, duration, or termination. Obviously, the discussion above on the conceptual and theoretical lacunae suggests that this approach is utterly inappropriate for fully capturing the dynamics of such a complex phenomenon as internal conflict. The conceptual and theoretical gaps must be translated into clear-cut methodological remedies. In other words, we need to do much better than merely stating that civil war has a greater likelihood of “happening” or “lasting” in a given country-year.

A first remedial step is to abandon the country-year focus and recast civil war in a dyadic perspective with the dyad-year as the main unit of analysis.54 Theories of war are dyadic: it is the strategic interactions between actors rather than national-level characteristics that shape war processes and outcomes. Cunningham et al. (2009) observe that civil war studies suffer from a failure to produce research at the dyadic level. Because conflict onset and duration are often endogenous to the bargaining between actors (who operate under certain structural constraints), a dyadic approach allows us to come up with more realistic, dynamic theories of internal conflict. The authors point out not only the analytical gains accrued with a dyadic approach, but also the difficulties of producing such dyadic data. For instance, it would not be feasible to come up with a list of all possible dyads. Hence—for now at least—we must be satisfied looking at a limited set of dyads.55

While the dyadic perspective is definitely a step forward, it needs to rest on a firmer theoretical and methodological foothold. The multiplicity of players in many civil wars may even suggest moving beyond a dyadic path. Some civil wars may be better explained in regional rather than dyadic terms. For example, would a dyadic approach be appropriate for explaining civil war onset and duration in Zaire (DRC) where so many internal and external players were involved in the break-out and perpetuation of hostilities? Moreover, our estimation procedures with the dyadic approach need to take into account that dyad-year observations may not independent of one another—subsequent observations for the same dyad over time and space may violate the independence assumption (Beck and Katz 1996; Beck 2007).

Another methodological remedy is to model the spatial and temporal dependence of conflicts more rigorously. Currently, there is a big mismatch between the dynamic civil war processes and the static, cross-sectional models being employed to capture them. If civil wars are temporally and spatially dependent, then we need to incorporate that empirical reality into our modeling strategies. This means going beyond standard corrections for temporal and spatial correlation in cross-sectional models56 and constructing properly specified duration and spatial regression models.57 The standard method for modeling temporal dependence has been to use time dummies or splines in logit models. Carter and Signorino (2010) show that time dummies can lead to estimation problems, and recommend using smoothed functions of time via a cubic polynomial or spline. As for spatial dependence, it is generally treated as a statistical nuisance rather than estimated properly. Ignoring spatial dependence in civil war research will tend to underestimate the real variance in the data. If a country’s level of violence is associated with a neighbor’s propensity for violence, this tells us something important about the regional distribution of violence. Hence, spatial association may be a substantive feature of violence rather than a simple statistical nuisance. If that’s the case, then the values of the dependent variable (violence) in country i are directly influenced by the values of the dependent variable in i’s neighbors, and a spatially lagged dependent variable model (SLDV model) may be appropriate.58

Another methodological remedy relates to where the covariates of civil war, onset, and duration are located. If theory tells us that they are to be found at both the macro-(or systemic) and meso-(or country) levels, then this needs to be clearly reflected in our model-building efforts. Hierarchical or multilevel models are well suited for capturing the interplay of causal factors located at different levels of analysis—these models incorporate the effect of explanatory factors from nested structures (subnational, national, systemic).59 Finally, if civil wars exhibit a wider range of possible outcomes than other types of wars as shown by Chapman and Roeder (2007), we could illuminate a war’s possible trajectories by using competing risks hazards models where the hazards of various civil war outcomes are modeled jointly rather than separately.60


  1. Top of page
  2. Abstract
  3. Civil War as a Conceptual Variable
  4. When Does a Civil War Really Begin or End?
  5. Civil War and Violence
  6. Systemic Causes of Civil War
  7. Are Civil Wars Fundamentally Different from Interstate Wars?
  8. A Closing Word on Methodology
  9. Conclusion
  10. References

Where do we go from here? I have pointed out throughout this article that before we are likely to make headway in reducing our collective ignorance about civil wars, the problem of what civil wars are and how best to measure them must be directly confronted. So, first and foremost, we must go back to better conceptualization of civil war in terms of its starting and ending points. Civil war may be a longer process than generally described in the existing literature. It may be the case that civil wars are longer-lasting phenomena that exhibit waves of escalation and de-escalation of violence occurring throughout a longer time frame.

Second, we have to turn back to theory. Specifically, we need theories of civil conflict that would be different from theories of civil violence. All quantitative civil war data sets conflate onset with violence. Violence is typically endogenous to civil war processes—therefore, it may be the case that a civil war actually starts (with group organization for collective action; arming; war declarations; de facto control over a territory) well before violence ensues.

Third, we have few systemic explanations of internal conflict. Systemic explanations zoom out lower-level dynamics; they locate the explanatory variables at a higher level of aggregation than current research does. A truly systemic-level theory of civil war would look for explanations at a higher level of abstraction than transborder effects or the presence of diaspora communities that are so prevalent in the extant literature on the external dimensions of civil wars. Such a theory would plausibly concentrate on macro-level factors such as patterns of state formation, or changes in international requirements for statehood that may encourage various forms of internal dissent.

Fourth, we need better theories that would enable us to determine whether civil wars are really different from international wars. Scholars (Posen 1993; Fearon 1995; Toft 2003; Walter 2004, 2009) have pointed to mechanisms that are common to both forms of conflict: credible commitment problems; security dilemma; indivisible issues. Nonetheless, existing theories do not take into account that warfare (interstate or intrastate) may be epiphenomenal to larger systemic characteristics that are related to the prevalent type of unit in international politics. Finally, we need to be more methodologically rigorous and pay closer attention to our unit of analysis, spatial and temporal dependence, and multilevel causality when building our models for civil war onset and duration.

All the above suggest that a lot more work needs to be done. Further progress requires fundamental changes in the way we think about and study such a complex phenomenon as civil war. No research program is truly progressive based solely on data collection efforts. The field does not suffer from a dearth of appropriate methodologies, but from a paucity of conceptual and theoretical insights. For the large-N civil war research program to advance in fruitful directions, small steps back to sounder conceptualizations, to better linkages between theory and data will actually represent great leaps forward.

  • 2

    Others have done so beautifully. See Blattman and Miguel (2010); Kalyvas (2007); Sambanis (2004); Tarrow (2007).

  • 3

    This phrase is attributed to Karen Rasler.

  • 4

    See Sambanis (2004). Many definitions of civil war overlap. Where there is disagreement, it’s usually in the operationalization of the concept.

  • 5

    On the transnational dimensions of civil war, see Salehyan (2009). The PRIO/UPPSALA data set classifies intrastate conflicts as either intrastate or internationalized intrastate wars.

  • 6

    Note that I purposefully refrain from using the notion of group and instead use collective actor or organization. I follow Brubaker (2004:16) who argues that collective actors or “organizations, not [g]roups as such, are the chief protagonists of [c]onflict and violence.” See also Sinno (2008:3), Vasquez (2008:25), and Wimmer (2002:97) for the view that organizations rather than groups are chief protagonists in both inter- and intrastate wars.

  • 7

    See the related discussion in Kalyvas (2006).

  • 8

    Based on a survey of the articles published in mainstream journals during the last decade, the most frequently used data sets are PRIO/UPPSALA; Fearon and Laitin (2003); Collier and Hoeffler (2004); Minorities at Risk; Correlates of War intra-state wars; Heidelberg KOSIMO; Sambanis (2004); Gleditsch (2004); Cederman, Wimmer, and Min (2010). See Sambanis (2004) for a discussion of civil war codings in many of these data sets.

  • 9

    In addition to counseling scholars to focus on conceptualization prior to operationalization, Sartori (1970:1042) also urges researchers to clearly state what specific concepts are not.

  • 10

    See Falleti and Lynch (2009) for a discussion of how careful conceptualization facilitates unit homogeneity (analytical equivalence).

  • 11

    The reader will have observed by now that I shunned from providing a definition of civil war that addresses at least some of the problems pointed out above. Definitional ambiguity may be ineluctable with a concept pitched at such a high level of abstraction. Nevertheless, I suggest that civil wars are (i) conflicts between a government and (a) collective actor(s) or between collective actors about incompatibilities in attaining various material and nonmaterial ends; (ii) which are generally fought within the territorial confines of a sovereign state but which have the potential to be regionalized/internationalized; and (iii) which exhibit various forms of violent and non-violent collective action from one episode to another (onset, escalation, de-escalation, termination).

  • 12
  • 13

    See Sambanis (2004) for a detailed discussion of coding problems in various civil war data sets.

  • 14

    There are actually two codings for civil war onset in this data set: one (Startdate) that marks the date of the first battle-related death and another (Startdate2) that marks the date when the 25 casualty-threshold is reached.

  • 15

    Obviously, start and end dates matter a lot for analyses of civil war onset, duration, and termination.

  • 16

    Diehl and Goertz (2000) classify enduring rivalries as those dyads that experience six or more MIDs during a 20-year period.

  • 17

    Because it relies on perceptions of enmity rather than on directly observable antagonistic behavior, the “subjective approach” needs a theory of both rivalry onset and rivalry termination. In the “conflict-density approach,” rivalry onset and termination are by definition.

  • 18

    See DeRouen and Bercovitch (2008) for tests of many rivalry hypotheses applied to enduring internal rivalries (EIRs).

  • 19

    In addition to an observable conflict outcome, the continued existence of armed opposition movements during peace years would also be a clear indicator that war has not really ended. I thank Jason Sorens for this point.

  • 20

    For the sake of exposition, I assume that we have sufficient time points to observe variation in the level of violence for the given country X.

  • 21

    Technically, in the latter two cases, we are dealing with non-stationary processes, and we have to difference the series to achieve stationarity.

  • 22

    Another substantive implication is that we need to “take time more seriously” in civil war research and better model duration dependence. See the discussion below.

  • 23

    A period of peace between violent episodes may actually be a time for reorganization and mobilization from either or all parties involved in conflict.

  • 24

    Existing codings could actually indicate this possibility: if an immediately posterior war onset is significantly more violent than a prior episode, then this may give credence to the “boiling container effect” of peace times on the probability of conflict recurrence.

  • 25

    A recent exception is Klein, Goertz, and Diehl (2008).

  • 26

    See Gibler and Tir (2010:951) for an account of similar problems in the rivalry literature.

  • 27

    On duration models, see Box-Steffensmeier and Jones (2004).

  • 28

    For an application of this estimator, see Metternich and Wucherpfennig (2011).

  • 29

    On the Zaire (DRC) conflicts, see Autesserre (2010).

  • 30

    On the origins of the Sri Lankan conflict, see Rotberg (1999).

  • 31

    With the following episodes: 1964—onset; 1965–1966—de-escalation; 1967—escalation; 1968–1976—de-escalation; 1977—escalation; 1978—termination.

  • 32

    With the following episodes: 1984—onset; 2001–2002—de-escalation; 2003—escalation; 2004—de-escalation; 2005—escalation; 2009—termination (with the observable military defeat of the Tamil Tigers).

  • 33

    Emphases mine.

  • 34

    By requiring an arbitrary minimum number of casualties to code for civil war onset, all existing quantitative civil war data sets conflate onset with violence.

  • 35

    See my proposed definition for civil war above.

  • 36

    The recent trend toward methodologically rigorous geospatial work on local, national, and transnational dynamics of conflict (Buhaug and Gleditsch 2008; Cederman, Buhaug, and Rød 2009; Raleigh and Hegre 2009; Buhaug 2010) suffers from the same “disaggregation bias”: these studies may purport to be about civil war, but they are really about violence. I thank an anonymous reviewer for bringing this point to my attention.

  • 37

    Contrary to the dominant view in the field (Chapman and Roeder 2007; Roeder 2007), I argue that the initial formation of many de facto states is not driven by war. In other words, many de facto states are not post-conflict institutional arrangements; rather, they are endogenous products of center-periphery interactions. If violence eventually breaks out, de facto statehood usually predates it and is typically the main casus belli. For example, the 1992 violence in Moldova over Transnistria occurred after pro-Russian actors established a state-like entity on the left bank of the Nistru river.

  • 38

    Bell (1973:118) situates more clearly this idea of a contested sovereignty situation when he argues that “civil wars tend rapidly to resemble wars of secession as the rival elites stake out areas of strength to which their supporters can drift.”

  • 39

    A contested sovereignty situation would offer a more reliable estimate of the exact start date for the 2011 Libyan civil war, for example. It is more realistic to consider rebels’ control over Eastern Libya as marking the beginning of the conflict rather than the moment when 25 battle-related deaths were registered.

  • 40

    Or, better put, to more or less violent forms of collective action.

  • 41

    Bargaining, information asymmetries, credible commitment theories of war are built around this core assumption about conflict writ large.

  • 42

    See Licklider (1993), Mason and Fett (1996), and Rosenau (1964) for other earlier efforts aimed at uncovering the strategic nature of internal conflicts.

  • 43

    The state can do that through direct repression (Davenport 2007) or third-party-sponsored violence (Regan and Norton 2005), for instance.

  • 44

    See Cederman and Girardin (2007:175) for an earlier call to “bring the state back in” civil war research.

  • 45

    Most of the covariates employed for testing hypotheses on civil war onset and duration are domestic (for example, regime type; state strength; level of development) rather than systemic.

  • 46

    Buhaug and Gleditsch (2008) embrace a similar view.

  • 47

    Emphasis mine. Gourevitch (1978), Regan (2000), and Akcinaroglu and Radziszewski (2005) also seek to grapple with the larger geopolitical determinants of internal violence.

  • 48

    See the special International Interactions issue [2009, Vol. 35 (3)] dedicated to the idea of applying IR theories to civil war. The potential analytical equivalence between inter- and intrastate wars is discussed at length in Cunningham and Lemke (n.d.).

  • 49

    While Toft (2003, 2006, 2010) looks at issue indivisibility as a constant that makes many wars irresoluble, for Goddard (2009) indivisibility is a variable.

  • 50

    I build on Cunningham et al. (2009) and Cunningham and Lemke (n.d.) in this paragraph.

  • 51

    The deficit of attention to nonstate actors in the extant IR literature is quite surprising because IR theories “are not logically restricted to the analysis of officially-recognized states” (Lemke 2008:774).

  • 52

    To my knowledge, only Wimmer and Min (2006) rigorously embrace this approach and focus on geographic territories rather than states as the units of analysis. This allows them to explain how the interactions among units are conducive to global or local wars or how different types of wars tend to co-evolve.

  • 53

    Cf. Cunningham et al. (2009); DeRouen and Bercovitch (2008).

  • 54

    See note above for the few recent studies that rely on the dyad-year as the main unit of analysis.

  • 55

    The authors suggest looking at armed insurgents who have shown a willingness to fight.

  • 56
  • 57
  • 58

    Ward and Gleditsch (2008) discuss this model in detail. The SLDV model resembles the more familiar autoregressive time-series model where temporal serial correlation is addressed by including a lagged dependent variable as a regressor. The SLDV model fits a parameter which captures the spatial dependence of observations on the characteristic of interest.

  • 59

    Hierarchical models can elucidate cross-level mechanisms that may affect the likelihood of civil war. One plausible mechanism would unfold as follows: protracted inter-state rivalry > (leads to) centralization of domestic power for extractive purposes in at least one of the rivals > (which leads to) resistance from certain segments of the population > (which leads to) > repression > internal war > regionalization/internationalization of war. On hierarchical/multilevel models, see Gelman and Hill (2007).

  • 60

    For an application of such models to conflict, see Bennett (n.d.).


  1. Top of page
  2. Abstract
  3. Civil War as a Conceptual Variable
  4. When Does a Civil War Really Begin or End?
  5. Civil War and Violence
  6. Systemic Causes of Civil War
  7. Are Civil Wars Fundamentally Different from Interstate Wars?
  8. A Closing Word on Methodology
  9. Conclusion
  10. References
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  • Arreguín-Toft, Ivan. (2005) How the Weak Win Wars: A Theory of Asymmetric Conflict. New York: Cambridge University Press.
  • Autesserre, Severine. (2010) The Trouble with the Congo: Local Violence and the Failure of International Peacebuilding. New York: Cambridge University Press.
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