Many theories of international relations assume that public opinion exerts a powerful effect on foreign policy in democracies. Previous research, based on observational data, has reached conflicting conclusions about this foundational assumption. We use experiments to examine two mechanisms—responsiveness and selection—through which opinion could shape decisions about the use of military force. We tested responsiveness by asking members of the Israeli parliament to consider a crisis in which we randomized information about public opinion. Parliamentarians were more willing to use military force when the public was in favor and believed that contravening public opinion would entail heavy political costs. We tested selection by asking citizens in Israel and the US to evaluate parties/candidates, which varied randomly on many dimensions. In both countries, security policy proved as electorally significant as economic and religious policy, and far more consequential than nonpolicy considerations such as gender, race, and experience. Overall, our experiments in two important democracies imply that citizens can affect policy by incentivizing incumbents and shaping who gets elected.

Do costly signals work? Despite their widespread popularity, both hands-tying and sunk-cost signaling have come under criticism, and there's little direct evidence that leaders understand costly signals the way our models tell us they should. We present evidence from a survey experiment fielded on a unique sample of elite decision makers from the Israeli Knesset. We find that both types of costly signaling are effective in shaping assessments of resolve for both leaders and the public. However, although theories of signaling tend to assume homogenous audiences, we show that leaders vary significantly in how credible they perceive signals to be, depending on their foreign policy dispositions, rather than their levels of military or political experience. Our results thus encourage international relations scholars to more fully bring heterogeneous recipients into our theories of signaling and point to the important role of dispositional orientations for the study of leaders.

Policy-makers and political scientists have long believed that states must make policy with an eye to maintaining a good reputation, especially a good reputation for resolve. Recent work, however, has argued that reputations for resolve do not form, and hence that past actions do not influence observers' behavior in subsequent interactions. This conclusion is theoretically problematic and unsupported by the evidence offered by reputation critics. In particular, juxtaposing reputation for resolve to power and interests is misleading when past actions influence observers' beliefs about interests, while the common approach of looking at crisis decision making misses the impact of reputation on general deterrence. We thus derive hypotheses about conflict onset from both the arguments of reputation critics and the logic of more standard reputation arguments, which we put to statistical test. We find that past action is closely connected to subsequent dispute initiation and that the effects of reputation generalize beyond the immediate circumstances of the past dispute. Although reputation is not all-important, leaders are well advised to consider the reputational implications of policy decisions in international conflict.Leaders often claim that a reputation for resolve is worth fighting for. President Harry Truman justified intervention in Korea on the grounds that a failure to respond "would be an open invitation to new acts of aggression elsewhere." 1 Justifying a firm policy by invoking concerns for the country's reputation may serve as an effective rhetorical tool to garner the public's support. But are leaders right to be concerned about their country's reputation for resolve? Does having a good or a bad reputation for resolve matter in international politics?Both policy-makers and international relations scholars traditionally have answered both these questions in the affirmative. However, drawing on a surprising dearth of evidence of reputation in the historical record, a growing literature argues both theoretically and empirically that states do not in fact develop reputations for resolution or irresolution. This conclusion suggests that leaders' efforts to build and protect those reputations have been wasted.

Hall, Todd and Keren Yarhi‐Milo. (2012) The Personal Touch: Leaders’ Impressions, Costly Signaling, and Assessments of Sincerity in International Affairs. International Studies Quarterly, doi: 10.1111/j.1468‐2478.2012.00731.x 
© 2012 International Studies Association What counts as evidence that the other side is sincere? Within mainstream international relations literature, scholars have focused on costly signals. We argue, however, that in the real world leaders do not simply look at costly signals, but they rely to an important extent on their personal impressions of other leaders, taking these as credible indicators of sincerity. Our approach thus builds both upon the literature on interstate communication and perceptions and upon more recent research in the field of neuroscience regarding affective information. To probe the plausibility of our theory, we focus on the indicators British Prime Minister Neville Chamberlain used to evaluate Germany sincerity in the late 1930s and Ronald Reagan employed to make sincerity judgments about Soviet intentions in the late 1980s. Additionally, we briefly discuss the 1961 Vienna Summit between Kennedy and Khrushchev as an illustration of how personal impressions can also result in negative assessments of sincerity. Our findings suggest that personal impressions are an important, but up until now relatively ignored, source of evidence for leaders of their counterparts’ sincerity with significant implications for threat assessments and policy choices.