In 2001, Richard Sobel published four case studies chronicling the impact of public opinion on U.S. foreign policy since the start of the Vietnam War. He used public opinion surveys and interviews with senior policymakers, including three secretaries of state and four secretaries of defense, to document how opinions fluctuated throughout each crisis and how various movers and shakers felt about the weight that they should assign to public opinion in their deliberations. The crises—the Vietnam War, the Nicaraguan Contra-funding controversy, the Persian Gulf War, and the Bosnia crisis—demonstrate that public opinion did constrain policy options, but did not determine the specific policies that were chosen. This finding confirms V. O. Key's theory, first expressed in his pathbreaking study Public Opinion and American Democracy (1961) that public opinion operates like a system of dikes. These dikes limit how far policymakers can go in committing the country to actions in the policy sphere.

Looking at public opinion data through the eyes of the very people who determine how much weight they will give to it in framing and defending their policy decisions provides a highly useful insider perspective on policymaking considerations. Nonetheless, one may question whether public statements and retrospective interviews truly capture the thoughts of publicity-conscious public figures. That concern is especially troubling in this case because many of the interviews were conducted in public settings during prominent news programs, rather than by the author in a more private, reflection-inspiring environment. Examining the actual performance of leaders, which Sobel does as well, may be a far better guide to what actually happened.

In addition to providing an interesting record about policy formulation, Sobel also uses the cases to test prevailing theories about the role of public opinion. As Ben Franklin said centuries ago in Poor Richard's Almanac, “There's many a slip twixt cup and lip.” Theories are one thing, practice is another, especially when it comes to democratic theories that postulate that in a democracy, vox populi, vox Dei—the voice of the people is the voice of God. Accordingly, the theory that emerges from the findings of Sobel's 2001 book, reinforced by its 2003 companion volume, is designed to be realistic. Sobel and Eric Shiraev, his later coauthor, label it as a “multi-axial” approach to indicate that complex political phenomena, like the impact of various public opinions on a variety of policies, must be examined from multiple perspectives. Each of these perspectives is composed of many testable variables that must be scrutinized in light of the specific socioeconomic, political, cultural, and psychological conditions prevailing at the time and place.

Sobel and Shiraev replicate the case-study-based approach to public-opinion impact research in their edited volume, International Public Opinion and the Bosnia Crisis. That book is unique because it tracks the public-opinion aspects of the crisis in eight countries: the United States and Canada, Britain, France, Germany, the Netherlands and Italy, and Russia. Each country chapter is written by experts familiar with the particular country's politics. The broad sweep through the political cultures of eight diverse countries allows for genuine comparisons. It also sheds fresh light on the validity of various prevailing theories, and permits the development of a complex theoretical framework that the editors explain in their coauthored introductory and concluding chapters in the volume.

For example, Sobel and Shiraev present a framework for assessing policy climate and testing the impact of climate factors on the interplay between public opinion and public policy. The main factors that create the policy climate are 1) the nature and functions of each country's political institutions and 2) the political status quo as it relates to a particular foreign policy. That includes the distribution of policy preferences among the public, as well as the bargaining strategies of national decision makers. As a third factor, the editors mention 3) the dominant value structures that shape the policy climate. For instance, Canadians, deeply concerned about humanitarian values, favored intervention in Bosnia from the start. By contrast, their Russian counterparts were initially neutral but then became aggressively negative, largely because of increasingly anti-American and anti-NATO sentiments. The fourth climate factor relates to 4) the contemporaneous framing of the foreign policy issue, which depends heavily on the nature of mass media coverage. Differences in these four factors explain differences in public opinion climates.

To elaborate a bit more on just one of these factors, when it comes to political institutions, public opinion has more impact in two-party than in multiparty parliamentary systems, probably because one can rarely talk about genuine majority opinions in multiparty systems. The respect for public opinion shown by political parties and interest groups also determines its influence, as does the degree of consensus among elites and between elites and the public. Unstable political parties are unlikely to recommend forceful foreign policy actions. Opinion guidance is strongest in presidential systems, especially when presidents happen to be popular.

As in Sobel's earlier book, he and Shiraev conclude from the comparisons of policy developments in multiple nations that there is substantial correspondence between policies and public opinions and a reluctance by policymakers to defy an overwhelming public consensus. Public opinion appears to be relatively stable everywhere, and people are universally reluctant to risk casualties. The precise impact of public opinion on policy depends on the context and on mediating variables, such as the effectiveness of networking among elites, elite awareness of public opinion, and the nature of the policy proposals. Military elites are far more likely to oppose military ventures than is true of civilian elites.

What major benefits flow from the comparative findings? One is the important realization that the term “public opinion” is interpreted in different ways, depending on each country's ideological and political context. Pollsters vary cross-culturally in the kinds of questions they ask about public policies and in the way they assess the strength of feelings and beliefs that support particular opinions. These differences have to be kept in mind when comparing reports about opinions held in different countries and at different times.

Similarly, policymakers have different motivations in heeding or ignoring public opinion. They may base their actions on ideological concerns, including the belief that democratic norms mandate attention to public opinion, or they may act on practical considerations that require evaluating many factors unrelated to the public's views. If practical considerations are paramount, policymakers who feel insulated from the wrath of the public may feel free to totally ignore it. If the public seems disinterested, which is often the case when foreign policy issues are at stake, governments everywhere are quite free in choosing the thrust of policies.

While most of Sobel and Shiraev's findings accord with familiar knowledge about public opinion, their contention that policy is more likely to change in response to a change in public opinion than vice versa is controversial. As an example, they point to the fact that public sentiment in various countries favored intervention in Bosnia long before their reluctant governments changed their minds. But that fails to acknowledge the well-documented “fait accompli” effect that suggests that publics will approve a policy they rejected earlier, once that policy has been adopted. The reversal helps people avoid the mental discomfort of having to live with a disliked policy. The crucial factors that explain whether publics or policymakers are more willing to change their views relate to the strength of the respective convictions and to the political circumstances at the time when decisions must be made.

Overall, the greatest benefit of this edited book for scholars, practitioners, and attentive publics is its usefulness for making well-considered predictions about the likely impact of public opinions on particular foreign policies. That usefulness will be enhanced if other scholars follow the patterns set out in these two books of examining multiple cases in a cross section of countries, using the same analysis and comparison criteria. Cross-cultural generalizations based on a single case, like Bosnia, regardless of the number of iterations, are bound to be shaky. Using the edited book as an analysis tool, policymakers need not even wait to see whether their predictions turn out to be accurate. They can use the criteria laid out by Sobel and Shiraev to guide the policy context in desired directions. Whether such public-opinion manipulations are a good or bad thing in specific cases is controversial, of course. The tools that scholars provide to policymakers are always double-edged, capable of doing good as well as producing harm.