It has been more than a century since Nietzsche proclaimed the death of God. The prophecy was widely accepted as referring to an alleged fact about increasing disbelief in religion, both by those who rejoiced in it and those who deplored it. As the twentieth century proceeded, however, the alleged fact became increasingly dubious. And it is very dubious indeed as a description of our point in time at the beginning of the twenty-first century. Religion has not been declining. On the contrary, in much of the world there has been a veritable explosion of religious faith.

Ever since the Enlightenment, intellectuals of every stripe have believed that the inevitable consequence of modernity is the decline of religion. The reason was supposed to be the progress of science and its concomitant rationality, replacing the irrationality and superstition of religion. Not only Nietzsche but other seminal modern thinkers thought so—notably Marx (religion as opiate of the masses) and Freud (religion as illusion).

So did the two great figures of classical sociology. Emile Durkheim explained religion as nothing but a metaphor of social order. Max Weber believed that what he called “rationalization”—the increasing dominance of a scientific mindset—would destroy the “magical garden” of premodern worldviews. To be sure, the two had different attitudes toward this alleged insight. Durkheim, an Enlightened atheist, saw modern secularity as progress. Weber was not happy about what he saw—ostensibly the imprisonment of modern man in the “iron cage” of rationality. But, happily or nostalgically, both agreed on what was supposedly happening.

Not to put too fine a point on it, they were mistaken. Modernity is not intrinsically secularizing, though it has been so in particular cases (one of which, as I will argue in a moment, is very relevant for the phenomenon of secularism).

The mistake, I think, can be described as a confusion of categories: Modernity is not necessarily secularizing; it is necessarily pluralizing. Modernity is characterized by an increasing plurality, within the same society, of different beliefs, values, and worldviews. Plurality does indeed pose a challenge to all religious traditions—each one must cope with the fact that there are “all these others,” not just in a faraway country but right next door. This challenge, however, is not the one assumed by secularization theory.

Looked at globally, there are two particularly powerful religious explosions—resurgent Islam and dynamic evangelical Protestantism. Passionate Islamic movements are on the rise throughout the Muslim world, from the Atlantic Ocean to the China Sea, and in the Muslim diaspora in the West. The rise of evangelical Protestantism has been less noticed by intellectuals, the media, and the general public in Western countries, partly because nowhere is it associated with violence and partly because it more directly challenges the assumptions of established elite opinion: David Martin, a leading British sociologist of religion, has called it a “revolution that was not supposed to happen.” Yet it has spread more rapidly and over a larger geographical area than resurgent Islam. What is more, the Islamic growth has occurred mostly in populations that were already Muslim—a revitalization rather than a conversion. By contrast, evangelical Protestantism has been penetrating parts of the world in which this form of religion was hitherto unknown. And it has done so by means of mass conversions.

By far the most numerous and dynamic segment of what I am calling this evangelical diffusion has been Pentecostalism. It began almost exactly one hundred years ago in a number of locations in the United States, as small groups of people began to speak in tongues and experience miraculous healing. From its beginning, Pentecostalism was actively proselytizing, mostly in America (though there were early outposts abroad—even, curiously enough, in Sweden). But the big Pentecostal explosion began in the 1950s, especially in the developing countries, and it has been intensifying ever since. The boundaries of Pentecostalism are somewhat vague: It is a multidimensional phenomenon, with explicitly Pentecostal denominations, local Pentecostal congregations with no denominational affiliations, and Pentecostal-like eruptions within mainline Protestant and Catholic churches. If one subsumes these groups under the general heading of charismatics, there are four hundred million of them, according to a recent study by the Pew Research Center.

Religious dynamism is not confined to Islam and Pentecostalism. The Catholic Church, in trouble in Europe, has been doing well in the Global South. There is a revival of the Orthodox Church in Russia. Orthodox Judaism has been rapidly growing in America and in Israel. Both Hinduism and Buddhism have experienced revivals, and the latter has had some successes in proselytizing in America and Europe.

Simply put: Modernity is not characterized by the absence of God but by the presence of many gods—with two exceptions to this picture of a furiously religious world. One is geographical: Western and Central Europe. The causes and present shape of what one may call Eurosecularity constitute one of the most interesting problems in the sociology of contemporary religion. The other exception is perhaps even more relevant to the question of secularization, for it is constituted by an international cultural elite, essentially a globalization of the Enlightened intelligentsia of Europe. It is everywhere a minority of the population—but a very influential one.

Secularism thus finds itself in a global context of dynamic religiosity, which means that it faces some serious challenges. We might distinguish three versions of secularism.

First, the term may refer to accepting the consequences for religion of the institutional differentiation that is a crucial feature of modernity. Social activities that were undertaken in premodern societies within a unified institutional context are now dispersed among several institutions.

The education of children, for example, used to occur within the family or tribe, but it is now handled by specialized institutions. Educational personnel, who used to be family members with no special training, must now be specially trained to undertake their task in teacher-training institutions, which in turn spout further institutions, such as state certification agencies and teachers’ unions.

Religion has gone through a comparable process of differentiation—what used to be an activity of the entire community is now organized in specialized institutions. The Christian Church, long before the advent of modernity, provided a prototype of religious specialization—the realm of Caesar separated from that of God. What modernity does is to make the differentiation much more ample and ­diffused.

One path for this development is the denominational system typical of American religion, with a plurality of separate religious institutions available on a free market. The American case makes clear that secularism, as an ideology that accepts the institutional specialization of religion, need not imply an antireligious animus. This moderate attitude toward religion is then expressed in a moderate understanding of the separation of church and state. The state is not hostile to ­religion but draws back from direct involvement in religious matters and recognizes the autonomy of ­religious institutions.

The second type of secularism, however, is characterized precisely by antireligious animus, at least as far as the public role of religion is concerned. The French understanding of the state originated in the anti-Christian animus of the continental Enlightenment and was politically established by the French Revolution.

This second type of secularism, with religion considered a strictly private matter, can be relatively benign, as it is in contemporary France. Religious symbols or actions are rigorously barred from political life, but privatized religion is protected by law.

The third type of secularism is anything but benign, as in the practice of the Soviet Union and other communist regimes. But what characterizes both the benign and the malevolent versions of laïcité is that religion is evicted from public life and confined to private space. There have been tendencies in America toward a French version of secularism, located in such groups as the American Civil Liberties Union or Americans United for the Separation of Church and State. What may be called the ACLU viewpoint is pithily captured in an old Jewish joke: A man tries to enter a synagogue during the High Holidays. The usher stops the man and says that only people with reserved seats may enter. “But it is a matter of life and death,” says the man. “I must speak to Mr. Shapiro—his wife has been taken to the hospital.” “All right,” says the usher, “you can go in. But don’t let me catch you praying.” The punch line accurately describes the ACLU’s position on any provision of public services (from school buses to medical facilities) to faith-based institutions.

All typologies oversimplify social reality, but it is useful to think here of a spectrum of secularisms: There is the moderate version, typified by the traditional American view of church-state separation. Then there is the more radical version, typified by French laïcité and more recently by the ACLU, in which religion is both confined to the private sphere and protected by legally enforced freedom of religion. And then there is, as in the Soviet case, a secularism that privatizes religion and seeks to repress it. Its adherents can be as fanatical as any religious fundamentalists.

All these types of secularism are being vigorously challenged. Even the moderate version of secularism, as institutionalized in an American-style separation of church and state, is being challenged by the contemporary religious movements that reject the differentiation between religious institutions and the rest of society. Their alternative is the dominance of religion over every sphere of human life.

For obvious reasons, most attention is now focused on the radical Islamic challenge. This challenge is represented by the ideal of a Shari’a state—that is, of a society in which every aspect of public and private life is subjected to Islamic law. Muslims differ as to whether this view is essential to the faith as proclaimed in the Qur’an or whether it is a later accretion that could be modified. Regardless, the call for an all-embracing Islamic state resonates strongly among contemporary Muslims. It is by no means limited to Jihadists, who want to establish such a state by violent means. Many Muslims who have no inclination toward terrorism or holy war have similar views.

Nor is such a view of religion dominating all of society peculiar to Muslims. The ideal of a Shari’a state has strong similarity with the ideal of a halakhic state propagated by some Orthodox Jewish groups in Israel. In India, the ideology of hindutva has similar ambitions, as have powerful groups within Russian Orthodoxy calling for a “monolithic unity of church and state” (a phrase used recently by a high official of the Moscow Patriarchate). In all these cases, the term fundamentalism is appropriate.

In progressive circles in America, comparable ambitions are frequently attributed to evangelical Protestants and Catholics. The attribution is empirically untenable. Only a very small minority of evangelicals, in the United States and elsewhere, want to set up a Christian state.

As to the Catholic Church, the last time it sought to establish a Catholic state was when it supported the Nationalist side in the Spanish Civil War. Since the Second Vatican Council, such a stance is unthinkable. Indeed, as Samuel Huntington has pointed out, the Catholic Church has become an important factor in democratization, notably in Eastern Europe, Latin America, and the Philippines.

One must make an important distinction between movements animated by genuinely religious motives and movements where ­religious labels are attached to agendas that are ­nonreligious.

Admittedly it is difficult to decide which motives are genuinely religious and which are not. There are, however, fairly clear instances of both. A suicide bomber in the Middle East may be trusted when he says that he is doing so to witness to the greatness of God. Social scientists (most of whom are quite secular in outlook) tend to believe that religious motives are suspect, that they are used to legitimate the “root ­causes” underlying a conflict. This is a bias that fails to understand the motivating power of religious faith.

And yet there are also clear instances of religious labels stuck on agendas rooted in very material interests. One such case is the Bosnian conflict, where religious markers were attached to clashes of political and ethnic interests. As P. J. O’Rourke once put it: There are three groups in the Bosnian conflict. They look alike, and they speak the same language. They are divided only by religion, which none of them believe in. Another case is Northern Ireland. And this case is again nicely illustrated by a joke: A gunman jumps out of a doorway, holds a gun to a man’s head and asks, “Are you Catholic or Protestant?” “Actually,” says the man, “I’m an atheist.” “Ah, yes,” replies the gunman, “but are you a Catholic or a Protestant atheist?”

A country in which the challenge to secularism is politically prominent right now is Turkey. The Turkish Republic was founded in 1923 by Atatürk, who was decidedly anti-Islamic and probably antireligious in general. He wanted to “civilize” Turkey, and civilization for him meant the secular culture of Europe. His political model was the French one—public life made, as it were, antiseptically free of religious symbols and behavior. Thus Atatürk proscribed the traditional fez as male headgear, insisting that Turkish men don European-style hats or caps. (This, by the way, had a very visible anti-Islamic implication: It is difficult wearing headgear with a visor in front to touch one’s forehead to the ground in the mandatory obeisance of Muslim prayer.)

This secularist ideology was firmly established in large sectors of Turkey’s society, particularly in the Kemalist political and military elite. It was dominant in urban, middle-class populations. Back in the Anatolian hinterland, a deeply Muslim culture continued to prevail, with people paying lip service to the Kemalist ­ideology but at the same time passively resisting it in family and community life.

In recent years, this resistance turned politically active. A series of avowedly Islamic parties entered the political process, challenging the Kemalist orthodoxy. For a while, the military intervened to stop such parties from taking power. But this has become progressively more difficult. One reason is that masses of Anatolians migrated to the urban centers, bringing their Muslim culture with them. Another is that Turkey (partly motivated by the elite’s desire to have the country admitted to the European Union) has become more democratic, and, as a result, all those unenlightened people are actually voting. And yet another reason is that some in the elite have come to doubt the old secularist orthodoxy and become lukewarm in their resistance to political Islam.

At present, an Islamist party is in power. Its leaders say they have no desire to overthrow the secular republic or to establish a Shari’a state. So far the military has not intervened, limiting itself to muttering threats. The most visible challenge from the religious side has been the insistence by many Muslim women on their right to wear the headscarf, the symbol of Islamic modesty, in public institutions—a practice still prohibited. (It is interesting how often headgear has become a flashpoint for conflict between secularists and pious Muslims—from the male fez to the hijab.)

The outcome of these Turkish debates has importance far beyond Turkey. The Pahlavi regime in Iran consciously tried to emulate Atatürk’s secular state. Again there was passive resistance by a strongly religious populace. And again the latter finally attained power. But the difference between the two paths to power clearly shows that the challenge to secularism can take very different forms: In Iran, an Islamic state has been set up by revolution and is marked by an oppressive dictatorship in which the Shi’ite clergy exercise hegemony. In Turkey, the Islamic party came to power through democratic elections, and thus far (though the Kemalists continue to have dark suspicions) it has not only observed the rules of the secular state but has actually made it more democratic.

What the two cases have in common was the blindness of the Enlightened intelligentsia to see what was coming. My only visit to Iran occurred in 1976, two years before the Islamic revolution. With one exception, all the intellectuals I met were opposed to the shah, and most of them expected a revolution. None of them expected the revolution that actually occurred, however, and I never heard mention of the Ayatollah Khomeini. About the same time, my wife was lecturing in Turkey. On her way through Istanbul, she noticed green flags (symbols of Islam) flying from houses and storefronts. She asked her host (an Enlightened university professor) whether these flags signified a resurgence of Islam. “Not at all,” replied the professor, “they are just put up by migrants from the provinces, ignorant people, who will never have much of an ­influence.”

On a much more recent visit to Turkey, I had an experience that may serve as a metaphor for the religious challenge to secularism, not only in Turkey but everywhere: A main tourist attraction in Ankara (indeed, just about the only tourist attraction) is the mausoleum of Kemal Atatürk. It is an imposing building, on a hill from which one gets a panoramic view of the city. At the time of my visit, in the center of the city one can see only one big mosque (built quite recently by the Saudis). Thus the city center, Atatürk’s capital, was quite literally a public space cleansed of all religious symbolism. But Ankara has expanded enormously since the 1920s, and the center is ringed by a great number of newer urban areas. As far as one can see, every one of these has a mosque. Thus Islam is besieging the capital of Kemalist secularism not only politically but physically.

Two instructive additional cases of a secular elite facing a popular religious challenge are India and Israel. When India became independent in 1947—and Nehru gave his famous speech celebrating India’s “tryst with destiny”—the new state was explicitly defined as a secular republic. No hostility to religion, Hindu or other, was implied by that phrase. After all, Gandhi served (and still serves) as a national icon. Mainly it was to set India off against Pakistan, which became independent at the same time, defined as a state for Muslims. By contrast, India was understood as a state in which all religious communities were to feel at home—Hindus as well as Muslims, Sikhs, Jains, and Christians.

India today is still defined in its constitution as a secular republic, in the sense of neutrality with regard to all religious communities. But, as a matter of fact, India is one of the most religious countries in the world, and more than 80 percent of its population is Hindu. Inevitably, this has political repercussions. In recent decades, the Congress party, which had presided over the founding tryst, has continued to uphold the secularist ideal (which is why Muslims mostly vote for it). But the major opposition comes from a party rooted in a vigorous affirmation of Hinduism as the core of Indian civilization. And the party, now called the BJP, has periodically held power both in several states and in the Union government.

Israel is remarkably similar in its secular and religious dynamic. The state proclaimed its independence a year after India. It did identify itself as a Jewish state, but this identity in no way implied that it would be a state with Judaism as the established religion. Like India, Israel has been a democracy from its beginning, and its non-Jewish minorities of Muslims and Christians were supposed to be full citizens.

As it turned out, there have been tensions between the dual identity of Israel as a democratic and a Jewish state, especially since the acquisition of the Palestinian territories after the 1967 war. It is not surprising that Arab citizens of Israel have been uncomfortable as a result of these tensions. But what is directly relevant to the present topic is that many religious Jews have been uncomfortable by the secular, religiously neutral character of the state.

For a long time the political and cultural elite was strongly secular. There is no precise equivalent to India’s BJP in Israel, but the major opposition party, the Likud, has drawn much of its strength from Jewish voters who resent the secular elite (to be sure, for many reasons, not just because of its secularity). Again not surprisingly, many Arab citizens have been voting for Labor.

Yet another instructive case is the United States. The religious challenge to secularism has been an important fact of American culture and politics for the past forty years or so. Unlike modern Turkey, India, and Israel, the American republic was not created under a secularist banner. The American Enlightenment was very different from the French, and the Founding Fathers, though some were not particularly pious Christians, were certainly not antireligious. Nor did the First Amendment have a secularist intention but rather was intended to preserve peace between the different denominations of what was then a mainly Protestant nation.

This arrangement worked very well for a long time. And the circle of tolerance has expanded steadily—from the different Protestant denominations, to Catholics and Jews, and finally to just about any religious community that does not engage in illegal or clearly outrageous behavior.

What has changed in more recent times (I suspect, beginning in the 1930s) was what could be called a Europeanization of the cultural elite. This elite was increasingly secular, and its politics became increasingly secularist (a sort of Kemalization, if you will). All along, though, the general population continued to be stubbornly religious.

This religiosity, especially in its evangelical version, was looked down on by the elite. H.L. Mencken’s contemptuous treatment of evangelicals in his writings (notably in his account of the so-called Dayton Monkey Trial) ably represented this elite perception—and still does. To be progressive came to mean secular. The United States continues, by any measure, to be the most religious society in the Western world. Sooner or later, this situation had to lead to a political clash. Just as in Turkey, India, and Israel, the nonprogressive populace was going to rebel against the elite—and it was going to use the mechanisms of democracy to do so.

There were two clear flashpoints sparking the rebellion. Both involved the Supreme Court, the least democratic of the three arms of government: the 1963 prohibition of prayer in the public schools and the 1973 prohibition of laws against abortion. And, as a result, in a curious reversal of the earlier relation to class by the two major parties, Republicans won the allegiance of the religious rebels and Democrats reflected the secularist biases of the elite. In recent elections, it turns out, degree of religious commitment—Protestant, Catholic, or Jewish—was the single best predictor of how people were going to vote.

I think the positioning of the two parties was accidental; it might just as well have been the other way around. But once the dichotomous identification became established, secularists and strongly religious voters both became important elements of the two parties. They supply the activists—the people who write checks, who volunteer in campaigns, who ring doorbells, and who address envelopes.

All this is fascinating for any social scientist trying to understand contemporary cultural and political developments. Should it matter to anyone else? The answer is yes, if one is concerned for the future of democracy in the contemporary world.

There is the general view that fundamentalism is bad for democracy because it hinders the moderation and willingness to compromise that make democracy possible. Fair enough. But it is very important to understand that there are secularist as well as religious fundamentalists—both unwilling to question their assumptions, militant, aggressive, contemptuous of anyone who differs from them. H. L. Mencken was just as much a fundamentalist as William Jennings Bryan (though Mencken was wittier). There are fundamentalists of one stripe who think that religious tyranny is around the corner if a Christmas tree is erected on public property. There are fundamentalists of the other stripe who believe that the nation is about to sink into moral anarchy if the Ten Commandments are removed from a courtroom.

In plain language, fundamentalists are fanatics. And fanatics have a built-in advantage over more moderate people: Fanatics have nothing else to do—they have no life beyond their cause. The rest of us have other interests: family, work, hobbies, vices. Yet we too must be militant in defense of certain core values of our civilization and our political system. It seems to me that a very important task in our time (and probably in any time) is to be militant in defense of moderation—a difficult task but not an impossible one.

peter l. berger is director of the Institute for the Study of Economic Culture at Boston University. This essay, in a slightly different form, was delivered as a William Phillips Memorial Lecture at the New School for Social Research on October 10, 2007. Permission to publish it here is gratefully acknowledged.