Here is a thesis that experts can evaluate better than I: The issue of religion in politics is fundamentally different in the US from many other countries. In the US, it is mainly about majority opinions versus minority rights. In countries from Mexico to Myanmar, it is about the social functions of a single organized body, the clergy. This difference matters for everyday politics.
The US has always had a religious majority that has been divided among many Christian denominations, with other faiths also represented. The Constitution gives individuals the right to exercise their religions freely. It also prevents any religion from being “established.”
The classic questions of religion and politics in the US involve majorities versus minorities. Sometimes, a coalition composed of many denominations supports a policy (e.g., banning abortion) for reasons that include religious ones. Then the questions become: 1) Does the desired policy impinge on constitutional rights? and 2) Are religious reasons for the policy acceptable or desirable in the public sphere? At other times, the majority becomes adverse to a particular religion–Mormonism in the 1800s being a clear example. Then the same two questions arise, but now the majority threatens the minority’s free exercise.
In nations with a single dominant religion that is organized in a hierarchical fashion (Catholic countries, but also, perhaps, some Muslim, Orthodox, Buddhist, Lutheran, and Anglican countries, plus in some respects, Israel), the issue is different. These countries have an organized, institutionalized body: the clergy. Typically, the clergy has a history of delivering some public services to the nation as a whole. For example, there may have been a time when the Catholic Church ran and staffed almost all of the state-funded schools in a given country. Sometimes, there is also a history of violent reaction against the clergy as an institution. Priests were executed in the French and Mexican revolutions, for instance.
In these countries, the question is not directly about whether to enact laws consistent with religious values. The question is whether to entrust an organized group of people, the clergy, with particular social functions. At the anti-clerical end of the spectrum, the clergy or priesthood is seen as a bane on society. At the clerical end, it is seen as a bulwark. These positions are, in principle, separate from one’s opinions of theology and of policy issues. A person could agree with the Church on most topics but distrust the clergy, or vice versa.
Here are some practical consequences of the difference:
- In the US, when debates over policy have religious components, they are deeply divisive and feel existential. At least some other countries treat such debates as fairly routine. The divisive issues for them concern the prerogatives of the clergy as an institution. An interesting hybrid case is Ireland, where the ballot victory on same-sex marriage was greeted with joy, at least in Dublin. I think voters were pro-equality, they celebrated because they had defeated the Irish clergy, a (currently unpopular) institution.
- In the US, religious involvement in politics is usually mediated by officially secular political parties. The parties strive to assemble majorities by drawing people from several denominations. They typically recruit believers, not churches, into their ranks. In many other countries, each political party has a relationship with the main denomination, ranging from a formal partnership (e.g., for the Christian Democratic parties) to official hostility. Indifference may also be an option, just as a party can be neutral on other issues, but it will face questions about the clergy.
- In the US, it doesn’t really make sense to ask a candidate what she thinks of “the clergy.” You can ask her about abortion, God, her own faith, or the First Amendment, but there is no national clergy to have an opinion about.
See also: a typology of denominations; the political advantages of organized religion; religion and politics in the Muslim world and the USA; and on religion in public debates and specifically in middle school classrooms.