A Just War: From Principles of Theory to Factors of Ordinary Judgments

Conflict Resolution Quarterly. 2026.

Gajiyev A., Deviatko I. F.

This paper explores the factors influencing ordinary judgments of justice in warfare, drawing primarily on normative theories of just war. By examining the alignment between the philosophical principles of just war and ordinary normative judgments, we explore the extent to which lay moral evaluations of war are shaped by the principles articulated in normative just war theory. Specifically, we experimentally test whether ordinary judgments about the moral character of war are influenced by information cues concerning the existence of a just cause for war, the international community's assessment of the legitimacy of the political regime in the state against which the war is being fought, and the side responsible for initiating the conflict. Additionally, we hypothesize that information regarding domestic public support for a war may have an even stronger impact on ordinary normative judgments than the information cue regarding the initiation of the conflict. Using a factorial survey design (N = 103) with vignettes, we assess the main effects and pairwise interactions of these four experimental factors on participants' evaluations. Our findings reveal significant insights into the comparative influence of these factors on the perceptions of war by laypeople as just or unjust. Notably, the largest effect size was observed for the domestic public support factor, often overlooked or contested within traditional just war theory. These results underscore the importance of contextual and socio-political dimensions in shaping ordinary judgments of justice in warfare, offering a more nuanced perspective on the interplay between normative theory and ordinary moral reasoning.

Keywords: everyday social cognition, just war theory, ordinary normative judgments, ordinary judgments of military conflicts, moral acceptability of war