In the conflict studies literature, the term ‘diffusion’ refers to the spread of instability from one geographic area to another. The original conflict may be sub-national, national, regional and/or international in nature. Diffusion of conflict can take place internally within or externally beyond the geographic boundaries of the original conflict country or region. Diffusion is a two-way reflexive process between the area of the initial conflict and another area to which the conflict may spread via actors or ideologies. Diffusion can be either internally or externally driven and a mass- or elite-level led process. This process takes place within an integrated framework of permissive conditions and proximate causes. Permissive conditions are underlying factors that make a conflict prone to violence. Proximate causes are catalytic factors that trigger a violence-prone conflict situation to turn violent. Permissive conditions and proximate causes are both necessary, but neither are sufficient to make a conflict diffuse from one area to another (Brown 1996, 1-31, 571-601; Cordell and Wolff 2009; Gurr 1993, 161-201).
Four analytical misconceptions are widespread in addressing diffusion of conflict. Firstly, diffusion is often explained as a ‘spillover process’, a mechanical or natural contagion of violence from one area to another, implying that little or nothing can be done to stop it. This simplification is misleading and potentially dangerous as it misjudges the reasons for and ways in which conflict spreads and, thus, prescribes inadequate remedies for its prevention. Diffusion of conflict is neither inevitable nor uncontrollable. Conflict spreads as a logical consequence of choices made by people – acting either as individuals or in groups. Secondly, diffusion of conflict is often confused with continuation, escalation or intensification of violence. However, conceptually, these are different phenomena. Conflicts do not necessarily develop in a linear and logical fashion and may move back and forth between different stages of violence and non-violence. However, if a conflict becomes more violent, there are four different ways in which this can take place; namely, through continuation, diffusion, escalation and intensification of violence. Continuation is when the violent aspect of a conflict continues over time. Diffusion is when violent conflict in one geographic area directly or indirectly generates violent conflict in another area. Escalation occurs when new actors become involved in an already existing conflict within its confined geographic boundaries. Intensification is the process by which the violence itself increases. This includes both an increase in the number and nature of violent incidents. Although these are four analytically distinct phenomena, continuation, diffusion, escalation and intensification may occur simultaneously. In practice they often overlap and intertwine (Lobell and Mauceri 2004, 1-10; Peen Rodt 2009, 18-28). Thirdly, most conflicts, in one way or another, influence situations in other areas. For example, the geographic neighbours of a conflict country are usually influenced by the conflict, even if the violence does not diffuse beyond its original borders. Likewise, if a country or coalition is involved in wars on several fronts these are likely to influence each other. However, it is important to distinguish between ‘influence’ and ‘diffusion’ of conflict. The ongoing conflict in Afghanistan, for example, influenced the simultaneous war in Iraq, but this was not a case of conflict diffusion. The spread of violence across the Afghan border into Pakistan, however, is a diffusion of the original conflict. Finally, it is important not to confuse trans-border diffusion of conflict with trans-border conflict formations that have straddled borders from their inception. A regional conflict formation, for example, is different from a regional diffusion of a conflict. In the former the original conflict is regional in nature, whereas in the latter the original conflict diffuses to new areas in the region. The violent break-up of the former Yugoslavia is an example of a regional conflict formation.
For over half a century social scientists have used the term ‘diffusion’ to explain that social phenomena such as violent conflict spread from one area to another. Traditionally not much attention was paid to why and how diffusion of conflict takes place. The process was simply referred to as a spillover of violence, often explained through analogies of natural disasters, epidemics or domino-like reaction patterns (Hill and Rothchild 1986; Most and Starr 1980; Ross and Homer 1976, Siverson and Starr 1990). In recent years conflict scholars have increasingly challenged the spillover concept and offered alternative, more in-depth theoretical interpretations of diffusion processes. The contemporary use of the term ‘diffusion’ in relation to violent conflict refers to a complex interplay between sub-state, state, regional and international factors, which together make up an environment of permissive conditions and proximate causes in which instability spreads from one area to another (Brown 1996; Cordell and Wolff 2009; Simowitz 1998).
Before the Second World War the scholarship of violent conflict, reflecting the situation in the international security arena at the time, was focused on conflicts between countries. Scholars typically studied the possible escalation of such conflicts rather than the diffusion of violence from one area to another. Much attention was paid to conflicts between the European powers (later joined by the USA) fought out either on the European continent or in proxy wars in their respective colonies throughout the world. Following the end the Second World War the research focus gradually shifted to conflicts of ideology, in particular between the countries on either side of the Iron Curtain. By the end of the Cold War as wars were increasingly fought within rather than between countries, the study of conflict diffusion shifted to internal conflicts and their possible internationalisation through processes of diffusion and/or escalation (Brown 1996; Lake and Rothchild 1998; Wolff 2006).
Across academic disciplines contemporary scholars of violent conflict increasingly agree that for a conflict to spread from one geographic area to another a combination of permissive conditions and proximate causes must be in place. The key condition for a conflict to diffuse is a pre-existing division between groups in the society in question. Hostilities can only spread to a new area if underlying tensions between different groups already exist there. Permissive conditions provide a fertile environment, susceptible to catalytic factors, which in turn may ignite another violent conflict. It is important, however, to stress that the possibility that such a process can take place does not necessarily mean that it will (Brown 1996).
A variety of different permissive conditions and proximate causes can make conflicts violent. Brown (1996, 1-31 & 571-601) has synthesised the literature on the causes of conflict and identified four key categories of permissive conditions and proximate causes of conflict; namely, structural, political, socio-economic and cultural factors. Conditions within each of these categories, either individually or in combination, can cause the outbreak of a violent conflict. Brown’s study focused on the conditions of conflict, however, the reasons why conflicts start must be related to why they diffuse. This is not to say that the reasons are the same, but that they are related. Intra-state security concerns such as fears of secessionism or an uneven demographic make-up are examples of underlying structural factors that can create an environment more susceptible to pressures deriving from violent conflict elsewhere. Likewise, exclusionary political institutions, parties or ideologies enhance the likelihood of conflict diffusion. Economic underdevelopment or discriminatory economic systems create both economic and social conditions under which the spread of violence is more probable. Finally, cultural discrimination--i.e. in language policy, uneven distribution of cultural resources and difficult group histories--also make people more inclined to fight each other (Lake and Rothchild 1998; Peen Rodt 2009; Wolff 2006).
Proximate causes of conflict diffusion are the result of internal or external, elite- or mass-led strategies seeking to kindle existing group tensions in one area through direct or indirect influences deriving from current or previous hostilities in another. The following highlights but a few ways in which a conflict can diffuse to a new area once the underlying conditions are permissive. Violence can, for example, spread through refugee flows from an existing conflict, which upon arrival may change the demographic composition and local perception of existing group divisions in the host country. Likewise, conflict elsewhere may foster solidarity and mobilisation in other societies or demonstrate to different groups how events could unfold in their own situation should the existing power divisions change. In the literature this is referred to as the ‘demonstration effect’. Conflict in one area can, thus, cause groups in other areas to change their beliefs concerning the efficacy of the state and their political safeguards within the existing structures. In this way, the behaviour of actors in the original conflict can influence the perceptions of groups in other areas and make them re-assess their own group’s profile, strategy, demands and actions. It is important to stress that a conflict can spread both to areas directly linked to the original conflict through cultural, political, socio-economic and/or geographic ties or to areas physically and psychologically distinct from the original area of conflict through the ‘demonstration effect’ (Brown 1996; Lake and Rothchild 1998; Wolff 2006).
The existing scholarship has identified five ‘fear-producing environments’, where underlying conditions become permissive; proximate pressures become catalytic and diffusion of conflict, in effect, becomes more likely. These are: the weakening of institutional state structures or government breakdown; non-state actors undermining state sovereignty or empowering other domestic actors; changing balances of power between external actors or patrons; changing power or resource distribution among groups; and differences in the degree of integration and vulnerability of groups in the international system (Brown 1996; Lake and Rothchild 1998; Lobell and Mauceri 2004; Walter and Snyder 1999; Wolff 2006). Particularly in societies where existing institutional structures guarantee the economic, political and physical security of conflicting groups, weakening state structures increase tensions and may lead to a security dilemma, in which one group takes pre-emptive action to defend its own security, which in turn may be interpreted as threatening to another group, whose re-action may fuel a continuing spiral of violence. Increased tensions allow non-state actors such as Diaspora or foreign activists to question the legitimacy of a ruling regime and appeal for or offer support to dissidents, minorities, ethnic kin or other groups through trans-border networks. The more intrusive such measures are, the greater reactions they are likely to provoke from a group’s domestic opponents, risking a diffusion of violence into a new area of conflict. The international power balance between external patrons and changes within it are often decisive for developments between conflicting groups on the ground. Violence is unlikely to spread to societies where the division of power and resources among groups is perceived as stable and relatively fair. Such structures are, however, sometimes challenged by real or perceived repercussions on the distribution of power and resources by conflict elsewhere, which may lead to further tensions arising. Societies in which resources are scarce and the competition for them is fierce are especially vulnerable to pressures mounting from conflict elsewhere. Equally, the difference in the degree of economic, social and cultural integration of groups in the international system can explain why some groups are more susceptible to external proximate pressures of violent conflict than others. Different groups experience different levels of integration into international or regional structures, which in turn causes political, economic and cultural disproportion and often discrimination between so-called ‘in’ and ‘out’ groups. Groups that are less integrated and, thus, more vulnerable in the international system are more susceptible to external pressures of violence, because such groups have less to lose and more to gain from turning to violence (Brown 1996; Lake and Rothchild 1998; Lobell and Mauceri 2004; Walter and Snyder 1999; Wolff 2006).
There is often a significant gap between the theoretical definition of diffusion and conventional explanations of how and why conflicts spread. Popular accounts of conflict as something which can spread uncontrollably from one area to another are deeply entrenched in international diplomatic jargon, political commentary and journalistic take. Such explanations are not only analytically misguided, but dangerous as they imply that forces of nature rather than actions of people are to blame for the diffusion of conflict. This has lead to a widespread assumption and often-convenient excuse that little or nothing can be done to stop the spread of violence throughout entire countries or regions. Diffusion of conflict, however, is a logical consequence of decisions and actions taken by often-identifiable individuals, groups or governments, which are not necessarily immune to external pressures from actors seeking to prevent a conflict from diffusing. Under-appreciating the importance of deliberate decisions and actions taken by individual or collective actors, has both in the past and present resulted in international failures to prevent diffusion of conflict and has had serious implications for international endeavours in crisis management and conflict prevention worldwide (Brown 1996; Lake and Rothchild 1998). More appropriate applications of the theoretical definition of diffusion of conflict are provided in the examples above.
Brown, Michael E., ed. The International Dimensions of Internal Conflict. London: MIT Press, 1996.
Cordell, Karl, and Wolff, Stefan. Ethnic Conflict: Causes, Consequences, and Responses. Cambridge: Polity, 2009.
Gurr, Ted R. 1993. Why Minorities Rebel: A Global Analysis of Communal Mobilization and Conflict Since 1945. International Political Science Review 14, 2: 161-201.
Hill, Stuart, and Rothchild, Donald. 1986. The Contagion of Political Conflict in Africa and the World. The Journal of Conflict Resolution 30, 4: 716-35.
Most, Benjamin A., and Starr, Harvey. 1980. Diffusion, Reinforcement, Geopolitics, and the Spread of War. The American Political Science Review 74, 4: 932-46.
Lake, David A., and Rothchild, Donald, eds. The International Spread of Ethnic Conflict. Princeton: Princeton University Press, 1998.
Lobell, Steven E., and Mauceri, Philip, eds. Ethnic Conflict and International Politics. Basingstoke: Palgrave Macmillan, 2004.
Peen Rodt, Annemarie. 2009. Success? EU Military Conflict Management Operations: 2003-2009. PhD diss., University of Nottingham, UK.
Ross, Marc H., and Homer, Elizabeth. 1976. Galton’s Problem in Cross-national Research. World Politics 29, 1: 1-28.
Simowitz, Roslyn. 1998. Evaluating Conflict Research on the Diffusion of War. Journal of Peace Research 35, 2: 211-30.
Siverson, Randolph, M., and Starr, Henry. 1990. Opportunity, Willingness and the Diffusion of War. The American Political Science Review 84, 1: 47-67.
Walter, Barbara, F., and Snyder, Jack, eds. Civil Wars, Insecurity, and Intervention. New York: Colombia University Press, 1999.
Wolff, Stefan. Ethnic Conflict: A Global Perspective. Oxford: Oxford University Press, 2006.
Strang, David, and Meyer, John W. 1993. Institutional Conditions for Diffusion. Theory and Society 22, 4: 487-511.