Fads, Fevers, and Firestorms

We live in a contagious world. Financial panic in Thailand sweeps across Asia and engulfs Russia. HIV infects more than 34 million people worldwide. But what impact is globalization having on the spread of political ideas? As interconnected as today's world is, national borders remain surprisingly solid barriers against political contagion.

Stephen M. Walt
By , a columnist at Foreign Policy and the Robert and Renée Belfer professor of international relations at Harvard University.

Protests against high fuel prices in Europe. The rise and fall of communism. The Roman Catholic Church. Privatization. The campaign to ban land mines. Keynesian economics. The emergence of the territorial state. The domino theory.

Protests against high fuel prices in Europe. The rise and fall of communism. The Roman Catholic Church. Privatization. The campaign to ban land mines. Keynesian economics. The emergence of the territorial state. The domino theory.

Although these movements stem from diverse sources, all are examples of political contagion. Beginning in the Middle Ages, contagion helped spread the territorial state from Europe to the rest of the globe, bringing with it the infectious ideology of nationalism. Contagion occurred when Catholicism emerged from Rome and expanded worldwide, when a series of states embraced Keynesian economics in the aftermath of the Great Depression, and when the idea of privatizing state enterprises spread from then Prime Minister Margaret Thatcher’s England to a host of other countries. During the Cold War, fear of contagion lay at the heart of the "domino theory," which predicted that a single communist victory would spark a wave of additional gains. And contagion is visible whenever an uprising in one country inspires the citizens of another to follow suit, whether it was Eastern Europe’s successful revolt against Soviet rule in 1989, or the protests against rising fuel prices that swept through Western Europe in 2000.

The spread of political ideas and practices is not new. But as the flow of goods, money, people, and information renders national borders increasingly porous, many experts believe the potential for contagion is greater than ever. Optimists say these trends will accelerate the spread of democratic ideals, undermine authoritarian governments, and hasten the emergence of a more equitable world order. But pessimists worry that the permeability of state boundaries will facilitate the spread of extremist ideologies, enable dissident groups to coordinate their actions more effectively, and allow criminals, terrorists, and other unsavory types to spread trouble over wider areas. Those alarmed by U.S. hegemony also fear that globalization will facilitate the spread of American habits and institutions, thereby threatening weaker societies with cultural extinction.

Proponents of these diverging views share the belief that contagion is a powerful force in contemporary world politics. In fact, both those who fear contagion and those who embrace it are wont to exaggerate its impact. Although political contagion does occur — sometimes with powerful effects — the spread of political models is usually slower and less dramatic than optimists or pessimists expect. Fads get attention and may look powerful for a while, but most societies are still surprisingly resistant to outside influences.


Just as firms in the same market tend to imitate each other’s successes, countries emulate improvements perceived to have served other nations well. In the late 19th century, Japan became more powerful by imitating Western economic and military practices, while the Chinese and Ottoman empires soon languished because they were unable or unwilling to copy these innovations. The tendency to imitate success is most prevalent in the military (where the incentive to compete is obvious), but other examples of imitative behavior include the competition among European powers to carve out colonial possessions in the 19th century, the creation of the welfare state, and the spread of modern regulatory practices and public health policies.

Imitation also occurs when citizens in one country copy those in another. Such behavior is often relatively benign (as in fashion or music trends), but it can be more troublesome when political activities in one country induce others to engage in similar behavior elsewhere. The recent protests against high fuel prices began in France, but soon spread to Belgium, the United Kingdom, Germany, and even Israel. In this sort of contagion, a successful uprising can provide a blueprint for others and encourage them to believe that their own efforts will succeed. In extreme cases (such as the "velvet revolutions" in Eastern Europe), an initial upheaval can launch similar responses in other societies, leading to sudden and unforeseen shifts in the political landscape.

Contagious behavior, often referred to as "herd behavior" — or what economists more pretentiously call an "informational cascade" — occurs when the proper course of action is uncertain, and people rely on the decisions of others to inform their own actions. Those who choose first have a powerful effect on what others do later. Like a snowball gathering mass and momentum as it rolls downhill, these initial decisions cause a self-reinforcing accumulation of similar choices. In economics, this sort of behavior can lead to speculative bubbles and financial panics as investors stampede in or out of markets, mimicking what they see others doing. In politics, these dynamics can fuel a sudden outbreak of revolutionary activity, prompt voters to "bandwagon" behind the leading candidate, or cause an alliance to collapse if a single, visible defection induces the other members to back out as well.

Unfortunately, this sort of behavior can occur even if the initial choices were poor. As the famous example of the qwerty typewriter keyboard illustrates, early decisions can get "locked in" (thanks to their widespread adoption) even when better alternatives exist. If governments are prone to imitate each other, inferior policies may become the fad du jour. In the 16th century, for example, several European monarchies competed to build the biggest warships, even though these vessels were enormously costly and too large to be of much military value. Less comical examples include the spread of Prussian-style "scientific forestry" in the 19th century (which turned out to have deleterious environmental effects in several countries), the adoption of collectivized agriculture and other socialist policies throughout the post-colonial world, or the popularity of import substitution policies in Latin America during the 1960s. Thus, the belief that globalization will facilitate the spread of best practices may be too optimistic if states embrace new policies in part simply because they see others doing the same.

Political contagion can also occur when stronger actors impose their preferences on weaker ones. The most obvious and extreme form is military conquest: The European colonial powers imposed their own institutions on their colonial empires, the Soviet Union established Stalinist regimes throughout Eastern Europe, and the United States wrote new constitutions and school textbooks in order to strengthen democracy in postwar Germany and Japan.

Yet imposition often takes subtler forms. During the 19th century, Great Britain used its naval and economic power to force an end to the slave trade, thereby eliminating a global institution that had existed for centuries. Similarly, the sudden popularity of privatization in the 1980s was not due solely to its intrinsic merit or the example set by a few key countries. Rather, international financial institutions actively promoted the policy. The decision to privatize, therefore, was not a wholly free choice because it was often a prerequisite for obtaining financial assistance from the World Bank or the International Monetary Fund.

New ideas and political practices can also spread if a sufficiently large and powerful group of states adopts a common set of standards and forces other states to adopt those norms if they want to be part of the club. States seeking membership to the World Trade Organization (WTO) must agree to common standards on export controls, for example, and states that wish to join nato or the European Union (EU) must conform their own domestic policies (such as human rights and fiscal spending) to those of the existing members. The larger and more powerful the group — and the more others value the opportunity to join it — the greater its ability to force others to embrace similar political practices.

These insights also help explain how nongovernmental organizations (NGOs) and other seemingly weak actors are sometimes able to catalyze significant shifts in national, and even global, policies. As the International Campaign to Ban Landmines illustrated, NGOs and other advocacy groups accomplish relatively little until they generate enough political support to persuade a few significant states to endorse their program. Once a crucial "tipping point" is reached, however, other governments begin to sign on simply to avoid defying the emerging consensus. Over time, the number of states that embrace the new norm will exceed the number that reject it, making it easier to single out the latter for censure or ridicule and increasing the costs of noncompliance still further. In this way, small transnational movements can have unexpectedly large effects.

In each of these cases, what might appear to be a free choice is not really "free" at all. A state can always choose to remain outside the EU or the WTO, just as individuals are free to rely on a Commodore computer, a rotary telephone, or an eight-track tape player. But resisting a widely accepted standard is usually costly, and most states, like most people, will decide to conform to prevailing norms rather than disregard them.

Although such examples suggest that contagion is an increasingly widespread and potent source of international change, there are still impressive obstacles to the rapid spread of new political practices. For one thing, power continues to play a key role in effecting contagions: New ideas are more likely to travel if they have powerful partisans. To say that contagion is widespread simply reminds us that powerful actors exert more influence than weaker ones.

Moreover, the most important transformations in modern history — the spread of the nation-state, the development of markets as the primary mode of social exchange, the rise of representative government, and the acceptance of certain basic ideas about human rights — were hardly products of fads or firestorms. On the contrary, each of these developments spreads through a highly contentious political process lasting several centuries. This observation raises the obvious questions: What circumstances make contagion more likely, and what determines its speed and scope?


Just as outbreaks of disease are more dangerous when the infectious agent is highly contagious and many potential victims are exposed, political "epidemics" are more likely when a particular idea has mass appeal and many different societies are exposed to it. In particular, the following factors will determine just how far and fast an innovation may move:

Universal Appeal: Certain political movements are more likely to spread simply because they possess features that make them broadly appealing. Movements based on universal ideas tend to be more contagious since they are by definition applicable everywhere. Both liberalism and Marxism-Leninism were highly contagious for this reason. The case of Nazism offers a striking contrast: Although Hitler & Co. did attract a few sympathizers outside the German-speaking world, their claim that Germans were a "master race" entitled to subjugate others was bound to have limited appeal elsewhere. Political prescriptions based on "Asian values" or "Islamic economics" are unlikely to spread very far for essentially the same reason.

Moreover, political ideas will be more infectious when they promise widespread benefits at little or no cost. Other things being equal, an innovation that promises to solve a wide variety of social ills will be more contagious than an idea that makes more modest claims. Once again, both capitalism and Marxism-Leninism guaranteed to eliminate poverty, injustice, and tyranny — and both ideologies could point to a number of legitimate achievements. Given these features, it is not surprising that both attracted numerous converts, and that it took nearly a century before one of them was finally discredited. Economist Albert Hirschman suggests the spread of the Keynesian model occurred for similar reasons; it appeared more "scientific" than other economic approaches and gave capitalist governments the capability to address a variety of social problems without resorting to communist or fascist methods. Privatization offered similar claims on a less ambitious scale, as it promised to deliver better social services at lower costs, reduce corruption, and stimulate economic growth.

Of course, an idea that actually proves beneficial is likely to have more extensive and enduring influence, especially when it strengthens those who embrace it. Such an innovation will attract more imitators, and those who adopt the new practice will be more likely to survive over time. And the stronger they are, the greater their capacity to encourage others to follow suit. To the extent that democracy fosters economic growth, for example, states that embrace it will enjoy both immediate material benefits and will be in a position to support democratic transitions elsewhere. Thus, the gradual spread of free markets and representative government may be due in part to the intrinsic appeal of these ideas (at least in some parts of the world), but it may also reflect their contribution to the economic supremacy of 19th-century England and 20th-century America. England and the United States were wealthy and powerful in part because they adopted liberal institutions, and their wealth enabled them to defeat several nondemocratic challenges and promote the further spread of liberal ideals.

This example highlights another important feature of political contagions: namely, their ability to generate "increasing returns" — meaning that innovations become more valuable as they become more widespread. Consider the growing popularity of English. As the scope of global communications increases, so too does the need for a common language. Because the United States is the world’s largest market and the world’s most powerful country, citizens around the globe have a clear incentive to learn English. And as more and more people learn English, the benefits of knowing how to speak it increase even further. American power increases the desirability of knowing English, which in turn further enhances U.S. power.

Finally, political ideas are more likely to spread when adherents believe it is their duty to convert others. This feature is a hallmark of most great religions, as well as major ideologies like capitalism and Marxism-Leninism. Not only did these ideas offer guidance for organizing societies, but a key part of each ideology was the imperative of spreading the message.

Connectivity: The more extensive the connections between different groups, the greater the potential for contagion. This relationship is as true of social trends as it is for disease. Unless ideas and activities can move across borders, political contagion cannot occur.

As the scope and speed of global communications have grown over the last century, it has become increasingly difficult to confine events and ideas within one state’s borders. Globalization increases the potential for political contagion. These days, even strong authoritarian regimes find it hard to insulate themselves from outside influences. It is more difficult for weak regimes to resist these pressures, which may explain why political contagion has been especially endemic in post-colonial Africa, even though the continent has been slow to integrate into global economic and communications networks.

Improved global communications have made it easier for like-minded individuals and groups to coordinate their actions across national borders and to create more enduring and powerful transnational networks. Such groups include ethnic diasporas, drug mafias, the international scientific community, and a burgeoning array of NGOs and advocacy groups. These groups facilitate political contagion in at least two ways.

First, transnational networks serve as "transmission belts" for particular policy initiatives. During the Cold War, for example, the transnational "Pugwash movement" (named for a village in Nova Scotia where the first conference took place) enabled Soviet and Western scientists to discuss a wide variety of nuclear issues and played a major role in efforts to limit the risk of nuclear war. Similarly, an ad hoc network of human rights groups has helped institutionalize emerging global norms against torture, arbitrary arrest, and other abuses, thereby constraining what governments are able to do at home and shaping what they are obligated to do abroad.

Second, transnational networks also provide material support to sympathizers in other societies. The Soviet Union created the Communist International (COMINTERN) in order to spread revolution (and to advance its own foreign-policy goals), and other revolutionary states have provided similar forms of assistance to like-minded foreign groups. Ethnic diasporas offer other examples: Irish-Americans provided financial support for the Irish Republican Army, and the Tamil Tiger guerrilla movement in Sri Lanka depends on remittances from Tamils in other countries. Similarly, Islamic mujahedin in Sudan, Pakistan, and elsewhere are recruited and trained in a network of religious schools, supported by money from wealthy Arab states.

The ability to generate contagious behavior also depends on the role that different groups occupy within a particular network. In his book, The Tipping Point, Malcolm Gladwell argues that social epidemics are triggered by two special kinds of people: "mavens" and "connectors." Mavens have special information about some set of choices (what to wear, where to eat, which movies to see, etc.). Connectors have a large and diverse array of acquaintances. When a maven tells a connector what to do, the information will spread further and faster and is more likely to spark a powerful, self-perpetuating trend.

This argument suggests that NGOs will be more influential when they possess information that is not readily available elsewhere, and when they are linked to a diverse array of organizations. If labor groups speak only to each other, they will have less impact than if they link with environmental activists, educators, academics, and celebrities. In short, if you want to spread your ideas, make sure you have a lot of friends and make sure they aren’t all alike.

Gladwell’s argument also underscores why great powers like the United States are a common source of contagious political thought. Not only does the United States generate lots of new ideas, but it also has extensive contacts with many other countries. In the international system the United States is both maven and connector. It lies at the center of a large network of allies and clients, and it casts an enormous cultural shadow over the rest of the world. Its ability to spread ideas is further enhanced by the wealth and prestige of U.S. universities, which attract a growing number of foreign students. In addition to being immersed in U.S. culture, foreigners studying business, economics, law, and public policy in the United States also receive an education that stresses the virtues of free markets, democratic institutions, and the rule of law. For all these reasons, the United States is well positioned to spread its ideas even if the U.S. government does not try to impose American values directly. When it comes to U.S. cultural hegemony, American universities may be as powerful a weapon as the American military.

Similarity: Contagion is more likely among nations that already resemble each other. When two societies are roughly similar, a development that is popular in one of them is more likely to seem relevant and desirable in the other. In retrospect, it should not surprise us that the Soviet empire dissolved as rapidly as it did, because Moscow’s Eastern European satellites had nearly identical political institutions and a uniform desire to toss the Russians out. This point also suggests why events such as the "velvet revolutions" will be rare.

By the same logic, contagion is less likely to occur among states whose internal characteristics are different, just as diseases rarely spread from one species to another. Thus, pan-Arabism was a contagious force in the Arab world in the decades after World War II, but it was politically irrelevant everywhere else. Islamic fundamentalism and individual forms of ethnic nationalism are equally self-limiting. They are by definition confined to areas occupied by a particular type of people. Even modest differences may be enough to immunize a society from a political epidemic: Although the collapse of communism in Eastern Europe did inspire the pro-democracy demonstrations in China in June 1989, the demonstrations failed to undermine the Chinese government and had little or no effect in communist Vietnam, North Korea, or Cuba.

These features also explain why contagion is most likely within particular geographic regions. States that are close to one another tend to trade more with each other and share higher levels of migration, tourism, and communications flows. Neighboring states are also more likely to have similar internal characteristics, in part because earlier waves of contagion affected them in similar ways. Thus, Latin America is predominantly Catholic and Spanish-speaking because it shares a legacy of Spanish colonial control, and the Arab world is predominantly Muslim because Islam originated in Mecca and spread primarily through military conquest. New ideas may travel well within a particular region but have little appeal farther afield. People may think globally, but they still act regionally.


Although unexpected waves of change do occur on occasion, its effects are rarely as rapid or far-reaching as many hope or fear. There are at least three good reasons for these limits.

First, despite the expansion of global markets, the growth of global communications, and the spread of English, the world remains deeply fragmented across ethnic, religious, linguistic, economic, and geographic lines. National borders are not simply lines on a map or legal conveniences; they also mark important social and cultural boundaries. Ironically, because the territorial state was itself a highly contagious and robust innovation, the world is now divided in a way that makes it more difficult for other political trends to spread as freely. And even if globalization has increased the potential for contagion, new ideas invariably evolve as they spread from one society to another. Capitalism takes distinct forms in each country, and the same is true for democracy, Catholicism, and other contagious ideas. The world is more tightly connected and borders are more permeable, but we are still a long way from a single world society or a uniform global culture.

Second, political contagion usually provokes countervailing tendencies that limit its potential. A revolutionary movement may triumph in one country because it takes everyone by surprise, but its success will put other regimes on guard and make it more difficult for others to duplicate the experience. No one anticipated the Iranian revolution, for example, but the fall of the Shah and the emergence of a radical Islamic government there quickly led Iran’s neighbors to take steps to ensure that they did not suffer a similar fate. The revolution did evoke sympathetic responses in several Muslim countries, but it failed to ignite similar upheavals elsewhere. Similarly, when strong states try to spread their own principles too overtly, other states are likely to join forces to contain them.

Third, efforts to spread new ideas often experience diminishing returns. When a new idea emerges, states that are especially susceptible to it will succumb first. Over time, however, further expansion becomes progressively more difficult as the seeds of innovation fall on less and less fertile ground. Contagion can even be self-defeating if spreading an ideal costs more than it is worth. For example, although U.S. leaders worried about falling dominoes throughout the Cold War, the gains the U.S.S.R. made in countries such as Ethiopia, North Korea, Angola, and Afghanistan turned out to be liabilities rather than assets. If anything, these "victories" probably hastened the Soviet Union’s ultimate collapse by draining Soviet resources and strengthening U.S. resolve to contain communism.

For all these reasons, rapid political epidemics are rare. Fads do arise, and firestorms do break out, but the novelty often wears off and the fires often consume themselves. In today’s world, contagion is more likely to take place through a gradual and nearly invisible process of learning and adjustment, rather than from a sudden and dramatic transformation in an entire social order. The term "contagion" suggests an uncontrollable and dangerous epidemic, but its most common form today may be the slow spread of regulatory norms over mundane issues such as food inspection, consumer product safety, pesticide use, accounting standards, and transnational litigation. The "silent epidemic" of global regulation is occurring in part because it is the product of transnational networks of lawyers, bureaucrats, and industry lobbyists who are largely shielded from intense public scrutiny. Because it is less likely to attract public attention, this sort of contagion is rarely seen as a threat to national autonomy and is less likely to trigger a hostile nationalist backlash. If one is looking for a metaphor for contemporary global change, therefore, the slow grinding of a glacier is a more accurate image than the plague.

Stephen M. Walt is a columnist at Foreign Policy and the Robert and Renée Belfer professor of international relations at Harvard University. Twitter: @stephenwalt

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