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⁵ Ibid., p. 39.

⁶ McMahan, Killing in War, p. 104.

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⁹ Jeff McMahan, “Rethinking the ‘Just War,’ Part 2,” New York Times, November 12, 2012, opinionator.blogs.nytimes.com/2012/11/12/rethinking-the-just-war-part-2/.

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¹² Feldman, Yuval and Lobel, Orly, “The Incentives Matrix: The Comparative Effectiveness of Rewards, Liabilities, Duties and Protections for Reporting Illegality,” Texas Law Review 87 (May 2010), pp. 1151–1211Google Scholar.

¹³ The margin of error for the entire sample is + / –4 percent.

¹⁴ Walzer, Just and Unjust Wars, p. 136.

¹⁵ Ibid., p. 127.

¹⁶ Ibid., p. 39.

¹⁷ William Shakespeare, quoted in ibid, p. 39.

¹⁸ Dill, Janina and Shue, Henry, “Limiting the Killing in War: Military Necessity and the St. Petersburg Assumption,” Ethics & International Affairs 26, no. 3 (Fall 2012), pp. 311–33CrossRefGoogle Scholar; and Christopher Kutz, “Fearful Symmetry,” in Rodin and Shue, Just and Unjust Warriors, pp. 69–86.

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²⁸ McMahan, “Rethinking the ‘Just War.’”

²⁹ McMahan, Killing in War, p. 108.

³⁰ McMahan, “The Ethics of Killing in War,” p. 730.

³¹ Jeff McMahan, “The Morality of War and the Law of War,” in Rodin and Shue, Just and Unjust Warriors, p. 29.

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³⁴ Los Angeles Times, Los Angeles Times/Bloomberg News Poll: George W. Bush/Congress/War in Iraq, USLAT2006-534 (New York: Bloomberg News, 2006), USLAT.092006.R47 (question number), Roper Center for Public Opinion Research, Cornell University, ropercenter.cornell.edu/CFIDE/cf/action/catalog/abstract.cfm?type=&start=&id=&archno=USLAT2006-534&abstract=.

³⁵ All the results presented in this paper are weighted to match the age, gender, race, and education statistics of the American population by YouGov. See Doug Rivers, “Pew Research: YouGov Consistently Outperforms Competitors on Accuracy,” YouGov, May 13, 2016, today.yougov.com/topics/finance/articles-reports/2016/05/13/pew-research-yougov.

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³⁷ All original stories used in our survey from which quotes were taken can be found in the appendix at the end of the article.

³⁸ The full text of all news stories, complete survey question wording, and replication data are available from the Harvard Dataverse, doi.org/10.7910/DVN/SFYG2G.

³⁹ It is possible that some subjects could have concluded that Eastland's counterattack was also unjust if they did not accept that the Westrian invasion gave Eastland a just cause for war. For example, some subjects may have felt that Eastland's counterattack was not a necessary or proportionate response to Westria's seizure of Eastland's territory and oil fields. Although this seems unlikely, a few scholars, such as Rodin (see War and Self-Defense, pp. 127–38), do contend that even an unprovoked military invasion of national territory does not always justify the use of force in self-defense (for a counterargument, see Steinhoff, Uwe, “Rodin on Self-Defense and the ‘Myth’ of National Self-Defense: A Refutation,” Philosophia 41, no. 4 [December 2013], pp. 1017–36CrossRefGoogle Scholar). Empirically, our results confirm that a large majority of subjects did perceive Eastland's counterattack as just. Indeed, more than five times as many subjects agreed that Eastland was justified in its counterattack than thought Eastland was justified when it launched an unprovoked attack on Westria. To the extent that some subjects believed that Eastland's counterattack was unnecessary or disproportionate, however, our results should be considered conservative.

⁴⁰ The analyst's statement that the troops would “fight hard and do whatever is asked of them” was included in the conditions of both the conscripts and volunteers to ensure that subjects would not assess Eastland's chances of winning differently across the conditions.

⁴¹ Although these conditions might appear to be double-barreled, we included a mention of conscription and the degree of Eastland's soldiers’ enthusiasm for the war in order to signal whether Eastland's soldiers have moral agency or are compelled to fight regardless of their personal feelings about the war. Thus, although the comparison between condition C and condition A cannot isolate the effect of conscription from the effect of soldiers’ beliefs in the war, it does allow us to isolate the effect of moral agency of Eastland's soldiers on the public's ethical assessments of the soldiers’ behavior.

⁴² Subjects who failed the manipulation check were asked to read the story again. On average, 84 percent of subjects answered the manipulation check correctly on the first attempt and all subjects answered it correctly on the second attempt.

⁴³ Although we cannot rule out the possibility that some subjects believed that the unenthusiastic conscripts had a special responsibility not to participate in an unjust war, this kind of moral reasoning would not be consistent with revisionist theory. Future research could explore the relationship between soldiers’ enthusiasm for the war's cause and public views about soldiers’ moral culpability.

⁴⁴ There were no statistically significant differences on this question between relevant conditions.

⁴⁵ Since we expected subjects’ beliefs that soldiers behaved unethically to correlate with higher support for legal punishments, we coded “not ethical” using the reverse scale of the dependent variable used in figures 2, 3, and 4.

⁴⁶ In the just war condition (E), 43 percent of subjects preferred no form of punishment at all, compared to 18.5 percent who preferred no punishment in the unjust war condition (D). In both conditions, more than 80 percent of subjects who supported executing the soldiers who had committed the war crimes also supported prison terms. The small number of subjects who supported execution but not prison sentences may have felt that prison was not a sufficient punishment for participating in war crimes.

⁴⁷ Crawford, Neta C., “Individual and Collective Moral Responsibility for Systemic Military Atrocity,” Journal of Political Philosophy 15, no. 2 (April 2007), p. 188CrossRefGoogle Scholar.

⁴⁸ Approximately half of these subjects, however, also indicated that they believed that Eastland's war was unjust, roughly twice the percentage of those who did not support prison for leaders and soldiers in this condition.

⁴⁹ Unsurprisingly, subjects who supported the death penalty were significantly more likely to approve of executing the soldiers who committed war crimes in condition D.

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⁵⁸ Louis Harris & Associates, Harris survey (Rochester, N.Y.: Louis Harris & Associates, 1971), forthcoming survey (31107588), Roper Center for Public Opinion Research, Cornell University. Only 53 percent of respondents said he was not justified (12 percent chose “Not sure”).

⁵⁹ Gary Jonathan Bass, Stay the Hand of Vengeance: The Politics of War Crimes Tribunals (Princeton, N.J.: Princeton University Press, 2000).

⁶⁰ Gallup, Gallup/CNN/USA Today Poll: Congress/Bush/War in Afghanistan/Enron/Business/Slavery, USAIPOCNUS2002-03 (Washington, D.C.: Gallup, 2002), USGALLUP.02JA25.R18, USGALLUP.02JA25.R19 (question numbers), Roper Center for Public Opinion Research, Cornell University, ropercenter.cornell.edu/CFIDE/cf/action/catalog/abstract.cfm?type=&start=&id=&archno=USAIPOCNUS2002-03&abstract=.

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⁶³ George C. Marshall, quoted in Luke Mogelson, “A Beast in the Heart of Every Fighting Man,” New York Times, April 27, 2011, www.nytimes.com/2011/05/01/magazine/mag-01KillTeam-t.html.