THE relation between religion and politics continues to be an important theme in political philosophy, despite the emergent consensus (both among political theorists and in practical political contexts, such as the United Nations) on the right to freedom of conscience and on the need for some sort of separation between church and state. One reason for the importance of this topic is that religions often make strong claims on people’s allegiance, and universal religions make these claims on all people, rather than just a particular community. For example, Islam has traditionally held that all people owe obedience to Allah’s will. Thus, it is probably inevitable that religious commitments will sometimes come into conflict with the demands of politics. But religious beliefs and practices also potentially support politics in many ways. The extent and form of this support is as important to political philosophers as is the possibility for conflict. Moreover, there has been a growing interest in minority groups and the political rights and entitlements they are due. One result of this interest is substantial attention given to the particular concerns and needs of minority groups who are distinguished by their religion, as opposed to ethnicity, gender, or wealth.
This article surveys some of the philosophical problems raised by the various ways in which religion and politics may intersect. The first two main sections are devoted to topics that have been important in previous eras, especially the early modern era, although in both sections there is discussion of analogs to these topics that are more pressing for contemporary political thought: (1) establishment of a church or faith versus complete separation of church and state; and (2) toleration versus coercion of religious belief, and current conflicts between religious practice and political authority. The second pair of sections is devoted to problems that, for the most part, have come to the fore of discussion only in recent times: liberal citizenship and its demands on private self-understanding; and  the role of religion in public deliberation.
Establishment and Separation of Church and State
While the topic of establishment has receded in importance at present, it has been central to political thought in the West since at least the days of Constantine. In the wake of the Protestant Reformation, European societies wrestled with determining exactly what roles church and state should play in each other’s sphere, and so the topic of establishment became especially pressing in the early modern era.
A religious body may be a “state” church in the sense that it has an exclusive right to practice its faith.
A church may be supported through taxes and subject to the direction of the government (for example, the monarch is still officially the head of the Church of England, and the Prime Minister is responsible for selecting the Archbishop of Canterbury).
Particular ecclesiastical officials may have, in virtue of their office, an established role in political institutions.
A church may simply have a privileged role in certain public, political ceremonies (for example, inaugurations, opening of parliament, etc.).
Instead of privileging a particular religious group, a state could simply enshrine a particular creed or belief system as its official religion, much like the “official bird” or “official flower.”
Note that these options are not mutually exclusive—a state could adopt some or all of these measures. What is central to them is they each involve the conferral of some sort of official status. A weaker form of an established church is what Robert Bellah (1967: 3-4) calls “civil religion,” in which a particular church or religion does not exactly have official status, and yet the state uses religious concepts in an explicitly public way. For an example of civil religion, he points to Abraham Lincoln’s use of Christian imagery of slavery and freedom in justifying the American Civil War.
Contemporary philosophical defenses of outright establishment of a church or faith are few, but a famous defense of establishment was given by T. S. Eliot in the last century (1936, 1967). Trained as a philosopher (he completed, but did not defend, a dissertation at Harvard on the philosophy of F. H. Bradley) and deeply influenced by Aristotle, Eliot believed that democratic societies rejected the influence of an established church at their peril, for in doing so they cut themselves off from the kind of ethical wisdom that can come only from participation in a tradition. As a result, he argued, such a society would degenerate into tyranny and/or social and cultural fragmentation.
Even today, there are strains of conservatism that argue for establishment by emphasizing the benefits that will accrue to the political system or society at large (Scruton, 1980). According to this line of thought, the healthy polis requires a substantial amount of pre- or extra-political social cohesion. More specifically, a certain amount of social cohesion is necessary both to ensure that citizens see themselves as sufficiently connected to each other (so that they will want to cooperate politically), and to ensure that they have a common framework within which they can make coherent collective political decisions. This cohesion in turn is dependent on a substantial amount of cultural homogeneity, especially with respect to adherence to certain values. One way of ensuring this kind of homogeneity is to enact one of the forms of establishment mentioned above, such as displaying religious symbols in political buildings and monuments, or by including references to a particular religion in political ceremonies.
Rather than emphasizing the distinctively political benefits of establishment, a different version of this argument could appeal to the ethical benefits that would accrue to citizens themselves as private individuals. For example, on many understandings of politics, one of the purposes of the polis is to ensure that citizens have the resources necessary for living a choice worthy, flourishing life. One such resource is a sense of belonging to a common culture that is rooted in a tradition, as opposed to a sense of rootlessness and social fragmentation (Sandel, 1998; MacIntyre, 1984). Thus, in order to ensure that citizens have this sense of cultural cohesion, the state must (or at least may) in some way privilege a religious institution or creed. Of course, a different version of this argument could simply appeal to the truth of a particular religion and to the good of obtaining salvation, but given the persistent intractability of settling such questions, this would be a much more difficult argument to make.
Against these positions, the liberal tradition has generally opposed establishment in all of the aforementioned forms. Contemporary liberals typically appeal to the value of fairness. It is claimed, for example, that the state should remain neutral among religions because it is unfair—especially for a democratic government that is supposed to represent all of the people composing its demos—to intentionally disadvantage (or unequally favor) any group of citizens in their pursuit of the good as they understand it, religious or otherwise (Rawls, 1971). Similarly, liberals often argue that fairness precludes devoting tax revenues to religious groups because doing so amounts to forcing non-believers to subsidize religions that they reject. A different approach for liberals is to appeal directly to the right to practice one’s religion, which is derivable from a more general right to freedom of conscience. If all people have such a right, then it is morally wrong for the state to force them to participate in religious practices and institutions that they would otherwise oppose, such as forcing them to take part in public prayer. It is also wrong, for the same reason, to force people to support financially (via taxation) religious institutions and communities that they would not otherwise wish to support.
In addition, there are liberal consequentialist concerns about establishment, such as the possibility that it will result in or increase the likelihood of religious repression and curtailment of liberty  While protections and advantages given to one faith may be accompanied by promises to refrain from persecuting adherents of rival faiths, the introduction of political power into religion moves the state closer to interferences which are clearly unjust, and it creates perverse incentives for religious groups to seek more political power in order to get the upper hand over their rivals. From the perspective of many religious people themselves, moreover, there are worries that a political role for their religion may well corrupt their faith community and its mission.
Toleration and Accommodation of Religious Belief and Practice
As European and American societies faced the growing plurality of religious beliefs, communities, and institutions in the early modern era, one of the paramount social problems was determining whether and to what extent they should be tolerated. One of the hallmark treatises on this topic remains John Locke’s A Letter Concerning Toleration. A political exile himself at the time of its composition, Locke argues that it is futile to attempt to coerce belief because it does not fall to the will to accept or reject propositions,  that it is wrong to restrict religious practice so long as it does not interfere with the rights of others, and that allowing a wide range of religious groups will likely prevent any one of them from becoming so powerful as to threaten the peace. Central to his arguments is a Protestant view of a religious body as a voluntary society composed only of those people who choose to join it, a view that is in sharp contrast to the earlier medieval view of the church as having authority over all people within a particular geographic domain. It is perhaps unsurprising, then, that the limits of Locke’s toleration are coextensive with Protestantism; atheists and Catholics cannot be trusted to take part in society peacefully because the former do not see themselves as bound by divine law and the latter are beholden to a foreign sovereign (the Pope). Still, Locke’s Letter makes an important step forward toward a more tolerant and pluralistic world. In contrast to Locke, Thomas Hobbes sees religion and its divisiveness as a source of political instability, and so he argues that the sovereign has the right to determine which opinions may be publicly espoused and disseminated, a power necessary for maintaining civil peace
Like the issue of establishment, the general issue of whether people should be allowed to decide for themselves which religion to believe in has not received much attention in recent times, again because of the wide consensus on the right of all people to liberty of conscience. However, despite this agreement on liberty of belief, modern states nevertheless face challenging questions of toleration and accommodation pertaining to religious practice, and these questions are made more difficult by the fact that they often involve multiple ideals which pull in different directions. Some of these questions concern actions which are inspired by religion and are either obviously or typically unjust. For example, violent fundamentalists feel justified in killing and persecuting infidels—how should society respond to them? While no one seriously defends the right to repress other people, it is less clear to what extent, say, religious speech that calls for such actions should be tolerated in the name of a right to free speech. A similar challenge concerns religious objections to certain medical procedures that are necessary to save a life. For example, Jehovah’s Witnesses believe that their religion precludes their accepting blood transfusions, even to save their lives. While it seems clearly wrong to force someone to undergo even lifesaving treatment if she objects to it (at least with sufficient rationality, which of course is a difficult topic in itself), and it seems equally wrong to deny lifesaving treatment to someone who needs it and is not refusing it, the issue becomes less clear when parents have religious objections to lifesaving treatment for their children. In such a case, there are at least three values that ordinarily demand great respect and latitude: (a) the right to follow one’s own religion, not simply in affirming its tenets but in living the lifestyle it prescribes; (b) the state’s legitimate interest in protecting its citizens (especially vulnerable ones like children) from being harmed; and (c) the right of parents to raise their children as they see fit and in a way that expresses their values.
A second kind of challenge for a society that generally values toleration and accommodation of difference pertains to a religious minority’s actions and commitments which are not themselves unjust, and yet are threatened by the pursuit of other goals on the part of the larger society, or are directly forbidden by law. For example, Quakers and other religious groups are committed to pacifism, and yet many of them live in societies that expect all male citizens to serve in the military or register for the draft. Other groups perform religious rituals that involve the use of illegal substances, such as peyote. Does the right to practice one’s faith exempt one from the requirement to serve in the military or obey one’s country’s drug policies? Is it fair to exempt such people from the burdens other citizens must bear?
Many examples of this second kind of challenge are addressed in the literature on education and schooling. In developed societies (and developing ones, for that matter), a substantial education is necessary for citizens to be able to achieve a decent life for themselves. In addition, many states see education as a process by which children can learn values that the state deems important for active citizenship and/or for social life. However, the pursuit of this latter goal raises certain issues for religious parents. In the famous case of Mozert v. Hawkins, some parents objected for religious reasons to their children being taught from a reading curriculum that presented alternative beliefs and ways of life in a favorable way, and consequently the parents asked that their children be excused from class when that curriculum was being taught. Against the wishes of these parents, some liberals believe that the importance of teaching children to respect the value of gender equality overrides the merit of such objections, even if they appeal directly to the parents’ religious rights (Macedo, 2000).
Similarly, many proposals for educational curricula are aimed at developing a measure of autonomy in children, which often involves having them achieve a certain critical distance from their family background, with its traditions, beliefs, and ways of life (Callan, 1997; Brighouse, 2000). The idea is that only then can children autonomously choose a way of life for themselves, free of undue influence of upbringing and custom. A related argument holds that this critical distance will allow children to develop a sufficient sense of respect for different social groups, a respect that is necessary for the practice of democratic citizenship. However, this critical distance is antithetical to authentic religious commitment, at least on some accounts (see the following section). Also, religious parents typically wish to pass on their faith to their children, and doing so involves cultivating religious devotion through practices and rituals, rather than presenting their faith as just one among many equally good (or true) ones. For such parents, passing on their religious faith is central to good parenting, and in this respect it does not differ from passing on good moral values, for instance. Thus, politically mandated education that is aimed at developing autonomy runs up against the right of some parents to practice their religion and the right to raise their children as they choose. Many, though not all, liberals argue that autonomy is such an important good that its promotion justifies using techniques that make it harder for such parents to pass on their faith—such a result is an unfortunate side-effect of a desirable or necessary policy.
Yet a different source of political conflict for religious students in recent years concerns the teaching of evolution in science classes. Some religious parents of children in public schools see the teaching of evolution as a direct threat to their faith, insofar as it implies the falsity of their biblical-literalist understanding of the origins of life. They argue that it is unfair to expect them to expose their children to teaching that directly challenges their religion (and to fund it with their taxes). Among these parents, some want schools to include discussions of intelligent design and creationism (some who write on this issue see intelligent design and creationism as conceptually distinct positions; others see no significant difference between them), while others would be content if schools skirted the issue altogether, refusing to teach anything at all about the origin of life or the evolution of species.
Their opponents see the former proposal as an attempt to introduce an explicitly religious worldview into the classroom, hence one that runs afoul of the separation of church and state. Nor would they be satisfied with ignoring the issue altogether, for evolution is an integral part of the framework of modern biology and a well-established scientific theory.
Conflicts concerning religion and politics arise outside of curricular contexts, as well. For example, in France, a law was recently passed that made it illegal for students to wear clothing and adornments that are explicitly associated with a religion. This law was especially opposed by students whose religion explicitly requires them to wear particular clothing, such as a hijab or a turban. The justification given by the French government was that such a measure was necessary to honor the separation of church and state, and useful for ensuring that the French citizenry is united into a whole, rather than divided by religion. However, it is also possible to see this law as an unwarranted interference of the state in religious practice. If liberty of conscience includes not simply a right to believe what one chooses, but also to give public expression to that belief, then it seems that people should be free to wear clothing consistent with their religious beliefs.