This article has two aims: (1) to identify the causal effect of income inequality on civil conflict and (2) to find the mechanism in which disadvantaged individuals can mobilize collective violence. Applying the Heckscher-Ohlin and Stopler-Samuelson theorems, this study hypothesizes that workers in land-rich countries – those who face contracted demand in the labor market and consequently a larger income disparity – will have a lower opportunity cost to engage in conflict as trade expands. Exploiting exogenous spatial variation in inequality due to the country’s factor endowment, together with time variation in tariffs arising from the economic liberalization, the work of this research documents a statistically significant and economically meaningful causal effect of inequality on civil conflict. Secondly, to identify the mobilizing effect of inequality, I test whether higher disparity in income distribution within an ethnic group breeds more rebellions initiated by the group. Esteban and Ray’s model claims that an increase in income inequality within an ethnic group makes collective violence more likely, because the poor within the group provide conflict labor, and the rich within the group provide resources for violence. By merging international census data that cover 115 million individuals from 221 ethnic groups with the groups’ conflict records, the analysis empirically identifies that when holding total ethnic income constant, within-group inequality that is proxied by the unemployment rate is strongly correlated with the group’s propensity to initiate armed conflicts. Shedding new light on the prevailing scholarly discord that exclusively chooses either one of class and ethnic cleavages as sources of intrastate violence, the findings of this study imply that if trade-induced labor market shocks increase within-group inequality, it motivates workers to participate in rebellions by lowering their opportunity cost of fighting and mobilizes ethnic collective violence by allowing the ethnic leaders to recruit combatants at a lower cost.

中文翻译：

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不平等对国内冲突的激励和动员作用：关注贸易引发的劳动力市场冲击

本文有两个目的：（1）确定收入不平等对国内冲突的因果影响；（2）找到弱势群体动员集体暴力的机制。应用赫克歇尔-俄林定理和斯托普勒-萨缪尔森定理，本研究假设，土地丰富国家的工人——那些面临劳动力市场需求收缩并因此导致收入差距更大的人——将有较低的机会成本参与冲突，因为贸易扩大。本研究利用国家要素禀赋造成的不平等的外生空间变化，以及经济自由化引起的关税时间变化，记录了不平等对国内冲突的统计显着性和经济意义的因果效应。其次，为了确定不平等的动员效应，我测试了一个民族内部收入分配差距越大是否会引发该群体发起的更多叛乱。埃斯特班和雷的模型声称，族群内部收入不平等的加剧使得集体暴力更有可能发生，因为族群内的穷人提供了冲突劳动力，而族群内的富人则为暴力提供了资源。通过将涵盖 221 个民族的 1.15 亿人的国际人口普查数据与这些群体的冲突记录相结合，该分析凭经验发现，在保持民族总收入不变的情况下，以失业率为代表的群体内不平等与该群体的经济状况密切相关。引发武装冲突的倾向。这项研究的结果为普遍存在的学术分歧提供了新的线索，即专门选择阶级和种族分裂之一作为国内暴力的根源，这项研究的结果表明，如果贸易引发的劳动力市场冲击加剧了群体内的不平等，它就会激励工人参与通过降低战斗的机会成本来控制叛乱，并通过允许民族领导人以较低的成本招募战斗人员来动员民族集体暴力。