Much of the world looks at the United States and sees a political culture that is saturated with religious discourse. In fact, however, the US political system is designed to be among the most fundamentally secular political systems in the world. The reason this seems counterintuitive for Americans and non-Americans alike is because there remains great confusion over what the term 'secular' actually means.
Whereas the US is stringent in allowing no singular religion special access above others to the political and legislative processes, England, for example, has an official Church of England. In practice, the English do a fairly good job of keeping their political discourse secular, such that the the nominal Church of England typically does not wield its political capital to disproportionately affect English political policy; but the very fact that England has an official state Church whose governor is also the English Head of State is actually a fundamental violation of secularism. In the US, where there is no official church, there are many loud religious voices in mainstream politics. Culturally speaking, the US is a more religious country than England, at least on a surface level (number of people who would identify as 'religious'). Yet US secularism is still very much alive and well.
Misunderstandings of secularism come from both the left and the right; and the primary form of misunderstanding is in fact common to both sides of the political spectrum. Whereas secularism is properly a form of plurality, designed to protect individual citizens with the freedom to believe in any religion, or not to believe at all, without the state adopting an official religious stance that would give one set of believers unequal preference over another *in the eyes of the state,* too many people seem to think that secularism simply means the opposition to religion in the public sphere.
On the left, then, we see atheists contort and tarnish the meaning of secularism by invoking it in opposition to any kind of political expression that draws on religious belief. On the right, 'secularism' is similarly mistaken for atheism, such that the basic protection that secularism offers is lost amid attempts to defend a vague set of implied 'Judeo-Christian' values within the national political tradition. These attacks on secularism, from both sides, have threatened to diminish its value and prominence within American history and political culture.
People on the left need to understand that secularism does not and should not prevent religious citizens from invoking religious beliefs publicly and standing for public office on platforms informed by general religious principles. People on the right need to understand that, whereas secularism protects their rights as individuals to believe freely without state persecution and to lobby for elected officials whose political choices are informed by religious belief, secularism also prevents a religious elected official from enshrining a particular religious doctrine in the law of the land.
In other words, secularism is a double-edged tool, designed to allow religious freedom to the extent that it doesn't infringe in any official, state-sponsored way, upon the belief systems of those who believe differently. An evangelical Christian candidate for the US Senate, for example, could campaign on banning same-sex marriage and even win, just as, theoretically, a fundamentalist Islamic candidate could campaign on banning Catholic Nuns from wearing the Habit; but once either of these candidates becomes part of the state, with the privilege of legislating, the same secular principles that allow them their beliefs as private citizens--as well as their right to campaign on such religious beliefs--also prevent them from imposing those beliefs on the belief systems of others.
In effect, then, there's no problem, as far as secularism is concerned, with broad expressions of religious faith in the public sphere. If an evangelical Christian candidate who is opposed to same-sex marriage can gain the trust and esteem of some voters (and the ire of others) by proclaiming that s/he opposes same-sex marriage, there's no reason why such a candidate should be prevented from expressing publicly those views, which are of course political as well as personal. But I would argue as well that such a candidate enters dangerous territory for respecting the secularist tradition in American politics if s/he seeks to enshrine a religious belief against same-sex marriage as law. Th difference between having policy positions informed by religious belief and having policy positions that amount to religious belief is crucial. An example of the former--'the Bible teaches me that marriage is between a man and a woman, and I don't want the government telling me otherwise'--is consistent with a secularist approach. An example of the latter--'the Bible teaches me that marriage is between a man and a woman, and I will do everything I can to enforce this at the state level'--is nothing short of an intent to violate secularist principles. In neither case does a secularist oppose the invocation of a religious belief in political context, as many on the left mistakenly desire; the problem with the second example is that it expresses intent to make the state favor a particular religious doctrine.
In summation, secularism is not about religious prevention, but religious tolerance; and religious tolerance is about protecting all religions equally from state sponsorship, and not allowing religious beliefs to become state policy.
