Transcending the ‘End of War’ Debate: Toward a Mechanism-Centered View on the ‘War on War'

Has war become obsolete? Some argue that macro-historical social processes are leading war into obsolescence, while for others that pattern is explained by the fact that war is a lingering potential outcome of international politics. I argue that both answers reveal a fundamental problem with the debate about the ‘end of war’. The focus on securing predictions about the end of war keeps analyses trapped in either a teleological or nomothetical linearity and overshadows the varied set of contingent mechanisms that allow for non-violent outcomes to prevail in contentious political episodes. The ‘War on War’ could benefit from analyses that asses shifting configurations of mechanisms in power politics.

he Russian aggression against Ukraine -and its potential escalation into a major power conflict -has brought interstate war once again to the headlines of world politics.However, empirical evidence of a long-term decline in the frequency of interstate war in general 1 -and major power wars, in particular -has inspired a rich debate about the prospects of war becoming obsolete as a social phenomenon.
Optimistic views about the prospects of interstate wars going extinct are based on the usual suspects of the liberal peace hypothesis -norms, democratic institutions, market institutions, and socio-economic interdependence (DOYLE, 1983;GAT, 2006;MOUSSEAU, 2019;MUELLER, 1989;O'NEAL and RUSSET, 1999;OWEN, 1994;PINKER, 2011;RUSSET and O'NEAL, 2001).In contrast, others argue that the costs of war have risen to an unbearable point because the very possibility of war means that countries must continually create capacities and be prepared for it (COPELAND, 2014;LEVY and THOMPSON, 2010).To be sure, the harsh reality of world politics in the last couple of years has made this debate sound quite foreign.Nevertheless, in this article, I critically examine the debate on the 'end of war' to propose a mechanism-centered approach capable of reconciling some of this debate's insights with the enduring and contingent nature of war.Joshua Goldstein's (2011) insightful framing of the decline of war as a 'war on war' reveals some crucial layers of the 'end of war' debate.The implicit analogy with other diffuse wars, such as the 'war on drugs' and 'war on terror', brings to the fore the teleology underlying the idea of the 'end of war'.On the one hand, the analogy shows more explicitly that the idea of eventually extinguishing war in world politics is sustained by a normatively oriented social effort.On the other hand, this focus on the possibility of ending war reveals that centering the debate around 'whether' war is obsolete conflates the retrospective assessment of 'why' war has not been occurring with prospective speculation about its potential (non-) recurrence.I argue that such conflation is the reason why scholars are bewildered by the resurgence of interstate violence, a conflation that may also get in the way of the very end goal of winning the 'war on war'.______________________________________________________________________________________________ 1 See (GLEDITSCH et al., 2013) for a detailed discussion on the empirical basis for such a claim.Although the question of since when has war been declining is important, the main focus here is on how scholars addressing war decline explain such a trend and which are the analytical and pragmatic implications of these explanations.
This problem arises because answers to the question of 'whether' war is becoming obsolete are caught in a 'general linear reality' trap (ABBOTT, 1988).Those who argue for the obsolescence of war embrace the teleology of the 'war on war' endeavor and base their hopeful prospects on the driving forces of sustained progress, through which they explain the decline of war.Countervailing arguments, in turn, rely on trans-historical, nomothetic fixtures of an anarchical international system to sustain that it is the continuous preparation for war and the prevailing latent threat of war that prevents it from happening.Not surprisingly, both sides of the debate can find empirical confirmation.International society has progressively condemned warfare, intensified its efforts in war prevention, and enabled non-violent solutions for political disputes (GOLDSTEIN, 2011;MUELLER, 1989;PINKER, 2011).However, at the same time, major powers have continuously increased their military capacity and allocated a large share of their budgets to war preparation, thus increasing the costs of engaging in war (COPELAND, 2014;LEVY and THOMPSON, 2010).Both sides validate their arguments, and both causes covary with their explananda, but they give competing explanations for them.In that way, the explanatory necessity of their claims could only be addressed by the (inaccessible) counterfactual inexistence of one or the other.This apparent contradiction reveals the general linear reality trap in which both sides of the debate fall.They both simultaneously superimpose a linear conception of the future into their reading of the past and build their visions of the future on such a reading.This contradiction also exposes the inherent challenge, widely debated by philosophers of science2 , of grounding explanation and prediction of social phenomena in invariant covering laws.In granting either a teleological or nomothetic linearity on (partially) 'constant conjunctions', both answers to the 'end of war' debate misconceive a set of complex unbounded processes for a bounded one, concealing the bundle of conflicting (and often open-ended) mechanisms that have hitherto set it forth.I argue that we need to transcend the 'end of war' debate to gain greater insight and better engage with the 'war on war'.
To that end, I provide heuristics for opening this black box of mechanisms underlying either answer to the 'end of war' debate.Mechanism-based explanations focus on unpacking the 'nuts and bolts' involved in the process of 'producing' singular ______________________________________________________________________________________________ instances of a phenomenon, instead of their counterfactual necessity (DONNELLY, 2019a;ELSTER, 2007).Epistemologically, this approach circumvents the "fundamental problem of causal inference" (KING, KEOHANE, and VERBA, 1994, p. 79) by embracing the overlap between the questions of 'how' and 'why' social outcomes (like war) are produced.Therefore, a mechanism-centered approach shifts our focus from unverifiable causal claims to constructing a portfolio of contingent open-ended 'single causes' that, by analogy, can provide actors with tools to intervene in the social world -to fight the 'war on war'.
I further argue that addressing the 'war on war' with a mechanism-centered approach requires a concept of war open to the intrinsic contingency of social processes.War thus need not be seen as a transhistorical phenomenon, but rather as one that is intrinsically contingent and escapes 'covering law' explanations3 .Instead of looking for bold accounts of 'why' war does not reoccur and 'whether' it has become obsolete, we should focus on 'how' non-military solutions to otherwise militarized outcomes of political contentious episodes have prevailed.As the escalation of the Russian aggression on Ukraine reminds us, interstate wars, and not least major power wars, remain very much in the realm of possibility in international politics, and engaging with that possibility seems crucial for it to remain a statistical noise -or even only a possibility.A mechanism-oriented assessment of the war on war does not overlook the contingency of war but builds on it to better address the persistent contentiousness of world politics.
In the remainder of this article, I argue for such a mechanism-centered assessment of the 'war on war' in three main steps.First, I discuss how both answers to the 'end of war' question are imbricated in the construal of the social world as a general linear reality, analytically restricting not only our understanding of the process in which war has become an increasingly rare phenomenon in world politics but also our ability to intervene in such a process.Second, building on scholarly debates about explanations in international relations, I discuss the epistemological and pragmatic advantages of using mechanisms to explain and intervene in the social world.Finally, I illustrate how a mechanism-centered approach to the 'war on war' can help us ______________________________________________________________________________________________ transcend the end-of-war debate; I briefly develop an example of a heuristic framework based on the notion of war as a particular form of contentious politics.The conclusion summarizes the argument and contends that we would be in a better position to understand the potential obsolescence of war and act on it if we shifted our focus to mechanisms.
The 'end of war' debate trapped in the cage of 'general linear reality' Producing useful explanations for socially relevant phenomena is a common endeavor in distinct branches of social sciences4 .The prospective debate on the potential 'end of war' has thus been intrinsically associated with its retrospective explanation.To predict 'whether' war will not reoccur, one must determine 'why' it has not reoccurred.However, this explanation most often involves invariant causal claims about the effects of a certain variable X on the relevant phenomenon Y -in this case, war (JACKSON, 2017;KURKI, 2006;LEBOW, 2014).These causal claims are formulated to limit uncertainty and built reliable knowledge that Y will follow X in most (if not all) instances (JACKSON, 2011, pp. 70-71).To that end, the scientific endeavor of explanation is to 'empirically' distinguish efficient causes of the phenomenon from confounding covariates.
However, as widely acknowledged by neopositivists, securing such a distinction is always a tentative enterprise due to the so-called 'fundamental problem of causal inference'.Simply put, every causal inference relies on the assumption that the observed outcome would not exist had the postulated cause been absent (BEACH, 2016, p. 16).As causal processes are factually irreversible, inference about causal claims can be only assessed through a 'potential outcomes framework', reliant on a strategy to 'measure' such a counterfactual world in a matching control group (RUBIN, 2005(RUBIN, , 1974)).Consequently, our ability to intervene in the world becomes predicated on 'general claims about how the world' 'is', based on the continuous and impossible quest for 'certain' 'knowledge about how the world' 'has been', and the assumption that this is 'most likely how the world' 'will be'.
As Abbot (1988, pp. 170-171) has put it, this strategy traps our knowledge in this apparently safe world of "general linear reality", which assumes that "the social ______________________________________________________________________________________________ world consists of fixed entities (the units of analysis) that have attributes (the variables)" that invariably "cause" one another.By focusing on logically ascertaining and empirically verifying causal claims that "work the same under all conditions" (TILLY, 2001, p. 23), we are, by definition, left oblivious to the historical contingency producing these entities, their attributes, and the relations between those attributes.
Ultimately, our ability to learn from history is confined to the construction of a linear nomothetical or teleological production of the present and, putatively, of the future.
Both answers to the 'end of war' debate intrinsically fall under this trap of a 'general linear reality'.In the remainder of this section, we assess them.

Socio-evolutionary progress and teleological linearity of the 'end of war' debate
At the core of the optimistic prospects for the potential obsolescence of war is a teleological notion of social-evolutionary progress, which reduces history to a prelude to the present.Several works on this perspective fall broadly into the so-called 'liberal peace theory' (DOYLE, 1983;OWEN, 1994).At least since Kant, the dissemination and consolidation of changing attitudes toward war are a central intuitive explanation for both the decline of war and its potential extinction (BOURKE, 1942).This perspective focuses on the individual and collective effects of democracy, the market economy, and cosmopolitan liberal values on the production of sustained peace (DOYLE, 1983;GARTZKE, 2007;MOUSSEAU, 2019;O'NEAL and RUSSET, 1999;OWEN, 1994).To be sure, this body of literature provides theoretically sophisticated arguments and a rich inferential debate about these causes and their interactive effects, whose minutia I will not unpack here.And yet it bases its argument on the selfpropelling properties of these progressive values and institutions.
Another central perspective on the obsolescence of war tries to bring in contingency by focusing on collective learning.Mueller (1989), one of the most effective contemporary advocates of this position, argued that the experience of mayhem in contemporary major wars has led leaders in the developed world to be more conscious of the perils of fighting wars against strong enemies and to devise strategies of concertation.Goldstein's 'war on war' focuses more specifically on the system of preventive diplomacy, mediation of conflicts, and peacekeeping established after World War II (GOLDSTEIN, 2011).In an effort to avoid repeating the traumatic events of the first half of the twentieth century, states have built an apparatus in the United Nations (UN) to prevent episodes of contention from emerging and to provide feasible non-military responses to resolve them.
This evolutionist narrative is explicitly expressed in Gat's work, whose theory of war (and its absence) relies on "an integrated human motivational complex, shaped by evolution and natural selection" (GAT, 2009, p. 571).War becomes obsolete as other means for attaining the desired moral, material, and sexual resources become more efficient (GAT, 2009, pp. 592-595).The psychologist Steven Pinker (2011) takes a deeper dive into human nature in search of explanations; in addition to acknowledging new escape valves for our 'inner demons', he theorizes about the unleashing of the 'better angels' of our nature.For him, human evolution is not only driven by egotistical predation and retaliation: our evolutionary programming is "an open-ended generative system" also equipped with empathy, moral sense, and reason (PINKER, 2011, p. 13).
Humans would be leaving war behind in their past, according to Pinker (2011), because the best features of human nature have been selected through a confluence of social-environmental processes.These processes include the monopolization of the legitimate use of force by the state, greater economic interdependence underpinned by cooperative exchange, feminization of cultural values, and cosmopolitanism.Per Pinker (2011), these processes make cooperative socialization and non-violent competitive socialization features of greater adaptive fitness.

Hence, although recurring in a modern open-ended version of the old rhetoric
of "invoking the first man to settle our disputes for us" (GELLNER, 1988, p. 23), Pinker's explanation (2011) for why war is declining ultimately lies in his close-ended account of the selective properties of the social environment.However, as Levy and Thompson (2010) argue, there are no reasons to believe that the consolidation of the state or world commerce have a deterministic effect on the long peace that Pinker attributes to them (GLEDITSCH et al., 2013).Although the 'civilizing process' behind the transformation of human attitudes toward violence seems to have clearer effects on political conflict, these are not as coherently prone to peace as Pinker ( 2011) assumes (JACKSON, 2003;ZARAKOL, 2014ZARAKOL, , 2011)).
I argue that the fundamental problem with such a perspective is its teleological linearity.Such teleology is intrinsic to the debate in which these scholars are engaged.To justify the claim of the potential 'end of war', they conflate highly Transcending the 'end of war' debate: towards a mechanism-centered view on the 'War on War' ( 2023) 17 (1)  e0006 -8/27 contingent processes and open-ended mechanisms with one univocal socioevolutionary process bound to progress.By focusing on supporting this causal claim, they build a linear vision of the future on a linear reading of the past, ignoring the more complex pathways that allowed the still very contentious international politics of recent decades to produce non-violent outcomes.

Fixtures of anarchy and nomothetical linearity in the 'end of war' debate
On the other side of the debate, several scholars argue that, paradoxically, the fact that the latency of war is a definitional feature of international relations -with states continually preparing to engage in it -has raised its costs to an unbearable point.
War and war preparation have been historically constitutive of the modern (European) state as a hub of authority and resources (ELIAS, 2000;SPRUYT, 1994;TILLY, 1992).
Continuous preparation for war would thus explain the absence of actual wars, due to deterrence.Schelling (1960) argues that the threat of force, rather than its use, has become a central instrument of international politics, especially after strategic nuclear weapons emerged, allowing for mutually assured destruction (MAD).Waltz (1981) argues that MAD substantially diminishes the risk of war, as states would have no reason to seek their survival by creating an ''Armageddon.
From this perspective, the world has been kept safe because of the maintenance of MAD.Snyder (1961, p. 226), however, pondered that the very certainty of MAD carries a paradoxical self-deterring feature, reassuring states that nuclear weapons would not be used unless in response to a first nuclear strike.In that case, MAD has no absolute effect on preventing conventional warfare.In fact, nuclearized states that were not facing MAD have not used 'nukes' against non-nuclearized states, and there have been instances where nuclearized states made military movements that could have led to retaliation regardless of MAD (SNYDER, 1961).Fear of nuclear destruction alone does not explain the lack of major power wars since World War II; however, it looms large in every strategic calculation.Although advocating the central role of MAD, Levy and Thompson (2010) ascribe the decline of war to its progressively high overall costs.Nuclear weapons are not the only deterrent in contemporary warfare: capacities for conventional combat are also increasingly deadly.For Levy and Thompson (2010), war has become unbearable because its costs are increasing and because its economic rationale has changed.Their argument still emphasizes that states are no longer willing to bear the costs of wars with increasingly destructive potential, but it also acknowledges that cost alone does not tell the whole story.The explanation must incorporate the relative costs of military instruments vis-à-vis other political instruments.
Paradoxically, those who deny the prospect of the 'end of war' see deterrence, upheld by the ever-present security dilemma of anarchy, as the ballast of peace.However, situations such as the Russian aggression on Ukraine in 2022 challenge the claim that nuclear weapons -and even MAD -have direct linear effects on war prevention.MAD seems to have protected Russia against direct NATO military involvement in Ukraine, and it has not deterred Russia from waging a war against a state whose partnership with NATO was growing ever closer.MAD also seems to have played a role in encouraging NATO's response to escalate to the most severe forms of retaliation and involvement in the conflict short of direct military participation.This case resonates with what the literature calls a stability-instability paradox, where MAD prevents strategic conflict but may encourage limited conflict (JERVIS, 1984, RAUCHHAUS, 2009).
Therefore, while these perspectives serve as a crucial reminder of the set of structures and configurations that maintain war as a latent potential outcome of international politics, their reading 'de'-historicizes such a configuration under the guise of a transhistorical law.Furthermore, there are some perverse implications when war reduction is explained by the deterring properties of the evergrowing destructive power of war.Such a view naturalizes war and incentivizes states to continuously mobilize resources toward war as the only poss ible solution This causal complexity can take many forms, including the open-ended effects of causes (multi-causality), multiple causes of effects (equifinality), and non-linear interactions among potential causes (ABBOTT, 1988;BEACH 2016, p. 17;GUZZINI, 2017b;HUMPHREYS, 2017, pp. 724-725,).Secondly, by demanding 'empirically measurable counterfactuals', efficient causation forgoes the understanding of how any single phenomenon was produced.The only grounds for 'really' knowing why any concrete instance of a phenomenon occurs is to subsume it to a general explanation, a covering law whose observable implications have been vetted by systematic analysis of the covariation between putative causes and the outcome -any other explanation "might not be 'really' causal" (JACKSON, 2017, p.

692).
These two shortcomings combined are a problem if we want to act in the world, as we lose sight of 'how' relevant outcomes are produced (HUMPHREYS, 2017;JACKSON, 2017).They prevent us from harnessing our understanding of the 'end of war' to inform social action designed to advance the 'war on war'.The debate about the 'end of war' is pressing exactly because a substantial part of society wants war to end.
War is not a normatively neutral phenomenon; it is an undesirable outcome.Useful explanations of phenomena should inform "concrete action steps […] to solve problems and resolve problem-situations", that is, to "enhance our practical capacity" to produce a desired rather than an undesired outcome (JACKSON 2017, p. 698).I argue that a mechanism-centered approach is fundamental to advancing such an endeavor.I follow Jackson's (2017) argument that, even if we refrain from ascertaining and verifying the generality of causal claims, we still draw on their theoretical abstractions to produce explanations.First and foremost, these generalizations allow for a 'problem-situation' to be classed as a phenomenon somehow similar to other instances of a given explanandum Y.These generalizations are the existing constitutive and causal theories about phenomena analogous to Y.With this previous knowledge about the production of an abstract class of Y, one can trace the contingent production of that specific outcome.This is not to reduce the explanation of a singular outcome to an 'if-then' law about Y but rather to build on available theoretical knowledge about analogous phenomena, to select "salient factors in the part of the causal net" that are contingently producing such events (HUMPHREYS, 2017, p. 721) 6 ."That generality is what bridges the gap between individual instances, and makes the explanation useful," by allowing for a tentative "manipulability" over the outcomes we want to affect (JACKSON, 2017, p. 703).
Transcending the 'end of war' debate: towards a mechanism-centered view on the 'War on War' The explanatory power of mechanisms thus relies on the analytical dialogue between the contingency of local causation and the abstractions afforded by homology and analogy with phenomena of a similar nature and in dialogue with the heuristics of theories about these phenomena 7 .This is a perspective similar to Beach's systemic view of mechanism as "a series of parts composed of entities engaging in activities" that come together to produce analogous outcomes (BEACH, 2016, p. 18).Donnelly (2019a), surveying the philosophy of biology more deeply, adds that processual mechanisms should be understood as "productively organized entities and activities" 8 .
The key logic is to go beyond entities and activities and highlight the 'configuration of their organization' 9 .Processual-relational approaches in the field of international relations and elsewhere have theorized the emerging properties of organizational configurations, which should also be captured by a mechanismcentered approach 10 .
In this sense, mechanisms are always embedded in a constitutive theory and scientific ontology about the social production of a given phenomenon, but they are not limited by their intrinsic simplifications.Scientific ontologies provide the metatheoretical lens for any explanation, the abstractions we use to term the entities, activities, and relations in the social world (JACKSON and NEXON, 2013).Constitutive theories mobilize this ontology to identify the specific configuration of entities, activities, and relations that allow us to class a problem-situation and explain how this configuration shapes the production of outcomes of interest (NORMAN, 2021).
While these abstractions do not allow for the sequence of events that can lead to an outcome to be deducted, they are necessary to identify contingent causal pathways in single cases and learn from the contingency of similar problem-situations.

Lucas de Oliveira Paes
(2023) 17 (1) e0006 -13/27 "highlighting correspondence or partial similarity" so that a phenomenon appears "comparable to something else in significant respects" 13 .It is thus the homological production of analogous outcomes that allows for explanatory insights to travel across  By analogy with similar phenomena, the mechanism-centered approach reifies Y as the productive activity of entity E, which is equally reified through a given ______________________________________________________________________________________________ 13 Oxford English Dictionary.Available at ˂https://www.lexico.com/definition/homology˃. 14 This is close to a combination of the strategies for identifying the "productive continuity" of mechanisms that Runhardt (2016) calls the 'regularities and causal process observations'.Although her work compellingly argues that the first is not necessary and the second is insufficient for causal inference, I believe her critique only holds if one seeks to infer efficient causality in a 'potential outcomes framework', against which I argue here.See also (BENNETT, 2016, pp. 37-39).
Transcending the 'end of war' debate: towards a mechanism-centered view on the 'War on War' (2023) 17 (1) e0006 -14/27 constitutive theorization.Hence, in drawing on homologies with previous productive accounts of Y, mechanism-centered analysis pulls the contingent threads of its explanations by breaking with such a descriptive causality.A prosaic example might be helpful: if we want to know 'why a car has stopped', by analogy, we use the idea of family resemblance to class our 'explanandum' with other phenomena, and so we mobilize a constitutive theory of what a 'car stopping' is, a type of entity E (a car) and its activity Y (stopping).To actually explain the motion of a car in a useful way, we need to unpack the entity itself as a set of intrinsic (i.e., the car's mechanics) and extrinsic (i.e., the driver's intentions, traffic signs, the pedestrian crossing) configurations of entities and activities that are contextually relevant for the car to stop or some alternative outcome.The connection between these entities and activities would be drawn in a dialogue with existing theories about the phenomenon at hand, and it would involve the use of abstract homologies with other configurations of entities and activities that we believe can lead to stopping -or not -a car.Analysts can, therefore, draw on such generality to build "some general statement [X] connecting factors with the outcome [Y]" (JACKSON, 2017, p. 702).
In other words, by using analogy and homology between a given explanandum and other existing phenomena, scholars can avoid the contingency of single-case causation and draw on existing theoretical knowledge to make sense of such contingency.Theories are thus seen not as positive assertions about a linear world, waiting to be falsified, but as generalized abstractions of a non-linear world, which just need to be sufficiently useful and accurate to explain the case under study.Multiple existing explanations can still be juxtaposed through abduction in a given case in order to infer the best local explanation, without making any claim about the general validity of theories15 .Grounded theory may be built on this locally identified casual pathway insofar as novel mechanisms challenging or refining existing explanations are identified, thus expanding our portfolio of mechanism-centered accounts of analogous The 'war on war' in the non-linear world of 'contentious' world politics.
In the mechanism-centered framework just outlined, the first step to understanding the mechanisms of the 'war on war' is to understand the class of analogous phenomena we want to explain and in which we want to intervene: war.
Although theoretical disputes are fierce when scholars discuss the general causes of war or why a given war broke out, they are considerably milder when it comes to defining war.Few would challenge the simplest dictionary definition of war as a "state To turn these loose definitions of war into an explanation of war or non-war outcomes, we must identify an 'ontological or constitutive theory' of its production.
Charles Tilly's contentious politics framework may offer the grounds for exemplifying such a mechanism-based explanation.It explains collective violence among social groups as a particular manifestation of contentious politics (TILLY, 2003, pp. 04-11).
Contentious politics, in turn, is conceived as interactions among "makers of claims", whose claims, "if realized, affect the interests of at least one of the (other) claimants" (McADAM, TARROW, and TILLY, 2001, p. 05).Taken as a particular form of political violence, interstate war might be conceived as a particular outcome of contentious politics.In this perspective, (modern) warfare is conceived as an instrument of political mobilization that prevailed in the configuration of the European state system and then became a common means of political socialization as the international system became globalized (DUNNE and REUS-SMIT, 2017;MAcDONALD, 2014;SCHENONI, 2021;TILLY, 1992).
Instead of overlooking historical contingency, a productive definition of war builds it in and then consciously abstracts from it.In the case of war, the state is reified These homologies and analogies allow for a dialogue between the contingent context of a given contentious war-prone situation and existing theories, the abstractions that can help make sense of that context.For example, consider two strong competing explanations for the decline of war: the theories of democratic peace and nuclear deterrence.Both theories can be seen through a rationalist ontology that can underpin a contentious politics explanation.Instead of focusing on whether democratic states fight each other or whether MAD prevents the escalation of conflicts, we should concentrate on the entities and activities that could produce alternative outcomes in situations of contentious politics.For instance, causal explanation in democratic peace theory involves breaking a set of states into their governments and constituencies, which are then further broken into concrete entities (i.e., branches of government, domestic pressure groups), whose activities (i.e., lobbying, protest) produce a non-war outcome in a contentious situation between two or more democratic states (FEARON, 1994;SCHULTZ, 2001;TOMZ, 2007;WEEKS and TOMZ, 2013).Causal explanation in deterrence theory, on the other hand, means breaking the state into a set of decision-  FUHRMANN and SECHSER, 2014;POWELL, 1990;SCHELLING, 1960;SNYDER, 1961).Deciding 'whether' war is becoming obsolete requires determining 'why' it has been in decline since the end of World War II.One way to explain this trend is through the inexorable evolutionary process toward greater sociability and rationality, in that case, war is on the path to obsolescence.Another way to address this issue is to focus on the latency of war, which pushes states to continuously raise the costs of war and paradoxically, would prevent war from happening.I have argued that, by seeking to categorically define 'whether' war is obsolete and will not reoccur, both perspectives overly seek to categorize the causes of war decline (the 'why'), conflating complex social processes with teleological or nomothetical driving forces that make us oblivious to the more nuanced insights on 'how' that has come to reality in different contentious events.
As the growing great power rivalry between the United States and China and the invasion of Ukraine remind us of the persistent peril of war in world politics, I argue that we get a more revealing assessment of this historical trend of war decline by diverting the question 'from why' war has declined 'to how' states achieved alternative outcomes to contentious politics in specific episodes of contention.To be sure, human endeavor seems to be at the heart of every battle won in the war on war, as it has created conditions for peaceful outcomes to thrive where they had not in the past.Yet for such an agency to guide additional steps on the 'war on war', we must understand the effective (inefficient) contingency of this agency instead of getting lost in either teleological or nomothetical disputes around general causal claims.
In this work, I sought not only to challenge the value of determining whether war is becoming obsolete but also to offer heuristics to transcend the self-imposed limitations of the 'end of war' debate.I argue that, instead of conducting empirical analysis to verify and judge competing causal claims, a mechanism-centered approach to the 'war on war' builds on the analytical heuristics underpinning these theoretical Revised by Karin Blikstad Submitted on April 07, 2022 Accepted on October 05, 2022 for war prevention, feeding this fundamental material process that sustains the risk of war.Fundamentally, it disregards the social endeavor involved in diverting potential wars to non-violent outcomes.It focuses on fixtures of anarchy that neglect Transcending the 'end of war' debate: towards a mechanism-centered view on the 'War on War'(2023) 17 (1) e0006 -10/27the fundamental contingent role of collective agency in deterring the latency of war from its potential realization.The linear understanding of the 'end of war' and the 'war on war'Building the 'end of war' debate on this 'general linear reality' prism poses some crucial problems for understanding and acting on the 'war on war'.By focusing on empirically verifying overarching causal claims about the decline of war to assess its potential obsolescence, we remain blind to the historical contingency of such a process.There are two ways in which 'general linear reality' prevents us from deriving useful knowledge from contingency and complexity.The first concerns the causal complexity involved in producing every social outcome, not least wars.
explanations have gained ground in the discipline of international relations precisely to unpack how causes produce effects(BENNETT, 2013; BENNETT and CHECKEL, 2014;GEORGE and BENNETT, 2005;WALDNER, 2012).The relation between the 'why' of causal claims and the 'how' of singular explanatory chains, however, is far from trivial.While some scholars argue that the focus should be on mechanisms as intervening variables linking causes and effects, others have sought to abductively identify the mechanisms involved in producing singular social outcomes, whose local causality could be contingently "transferable to other cases" (GUZZINI, 2017b, p. 754) 5 .Whereas the first tradition remains trapped in the same problems of causal inference, the latter can provide valuable heuristic insight to explain the recurrent production of analogous social phenomena.Yet mechanismcentered approaches have struggled to operationalize the linkage between contingency and generalization, which limits their ability to offer an alternative to the linear reality model and build cumulative knowledge that can travel across cases(CHECKEL, 2017, p. 412).
that mechanisms -through analogy and homology -allow us to escape the cage of the 'general linear reality' by drawing on abstraction and generalization pragmatically.Through analogy, we can identify a problem-situation as being similar to a class of existing phenomena.Through homology, we translate the theoretical knowledge we already have about the configurations of actors and activities that explained the production of outcomes analogous to those in the context of the case under analysis.Both analogy and homology involve a dialogue with previous empirical and theoretical knowledge about a given class of phenomena.

Figure 01
Figure 01 captures this idea schematically.As shown in (A), a 'general linear reality' perspective has a causal logic in which the effects pass from a cause X to an outcome Y through an equally invariant mechanism.The mechanism-centered perspective, however, overcomes the self-imposed limitations of linear perspectives by focusing on the many combinations of the multiple configurations of entities and activities -the mechanisms -that have produced other instances of Y.It uses a simplified abstraction to assign an outcome of interest to the same class of phenomena and identify the configurations of entities, activities, and relations producing this outcome.Previous explanations can be contrasted with this ontological framework to then organize contingency into an explanation.Hence, a mechanismcentered approach can rely on the generality of causal claims without losing nonlinearities and other causal complexities deriving from each singular instance of the given phenomena, as it abdicates determining the degree of generality of those causal claims.By analogy with similar phenomena, the mechanism-centered approach reifies

Figure 01 .
Figure 01.Mechanisms for transcending 'general linear reality' as a recognized claimant of sovereign authority over an indivisible population and territory, while its wars are reified as a means available to further contentious politics ______________________________________________________________________________________________ Transcending the 'end of war' debate: towards a mechanism-centered view on the 'War on War' (2023) 17 (1) e0006 -18/27 through the violent collective mobilization of military resources.In such a conception, interstate conflict is a highly contingent phenomenon, one among many other potential outcomes of contentious politics.This theoretically informed definition is a necessary but insufficient step toward explanation.By definition, states are constitutive of interstate war.Every single war is produced by states, but states engage in contentious politics also by other means.As outlined in the last section and illustrated in Figure02, tracing back the explanation of a phenomenon means breaking with its definitional reification.More specifically, the grammar of any X causal claim about war usually involves breaking any 'k' number of warring states into internal and external configurations of concrete entities and activities.Any explanation of why a given war occurred would then draw on homologies between the war-prone problem-situation under study and previous knowledge about configurations of entities and activities producing war in analogous contentious situations.Such a focus on homologous concatenations of mechanisms also allows us to consider alternative configurations that could have led to alternative outcomes.It gives a sense of 'manipulability' on which concrete action can be grounded to achieve outcomes other than war (JACKSON, 2017).

Figure 02 .
Figure 02.Mechanism-centered approach to war as contentious politics our ability to understand and intervene in the social world.Seeing war as an outcome of contentious politics is an example of such a dialogue between empirical contingency and theoretical abstraction since such a perspective emphasizes the contingency of war as one possible outcome of contentious episodes among states while it recognizes the recurring agonism of world politics.Instead of just probing the deterring effects of the high costs of war or the causal efficiency of liberal forces of progress, we need to examine configurations of entities and activities that have kept war solely as a potential outcome.A similar heuristic can be applied to other ontological commitments and constitutive theories of war.As the theoretical generality of constitutive and causal explanations is converted into identifiable concrete actors and activities, we can consciously use abstraction and reification to gain insight into the contingency of real-world phenomena.By further investigating the patchwork of shifting configurations of mechanisms in episodes of political contention among states, along with their multiple effects on violent and non-violent power politics, scholars would offer a pragmatic way of understanding the current battlefield of our noble quest for peace.In doing so, one ought to acknowledge the equifinality and multi-causality producing any single instance of war or peace, avoiding the risks of naturalizing the present and losing sight of the challenges ahead.By moving away from essentialist and deterministicteleological or nomothetical-causal claims, scholars can embrace the contingency of the social world; and that, to borrowTilly's (1996Tilly's ( , p. 1606) cautionary words, can help avoid leaving social scientists baffled by forthcoming plot twists in world politics.
armed conflict" among polities 18 .Of course, analytically, that does not say much.While such a dictionary definition identifies the relevant entities producing war (states), it gives little insight, descriptively, into the activity of producing war itself.Clausewitz's classic definition of war "as a continuation of political intercourse, carried of