Thus, once again we find a culture-war issue with social conservatives postured as defending moral absolutes, while liberals wander the treacherous landscape of relativism with a seemingly fluid sense of right and wrong. In a political environment, where "traditional values" have currency and complex ideas don't, the notion of moral absolutism often resonates, and “moral relativism” can be easily demonized by -mongering opportunists. If liberals have a problem with political posturing, few issues illustrate it better than the absolutism vs. relativism debate.

As modernity moves forward, there are constant tensions over challenges to traditional . The most obvious area is sex, where the advance of science and technology (especially birth control) has prompted reconsideration of many longstanding norms and taboos, revolutionizing society and transforming life in numerous ways. Not surprisingly, despite much progress, we see frequent hesitation and even fierce resistance to change, especially from pockets of deep religious conservatism.

When that resistance to modernity is vocalized, the rhetoric will often include references to moral absolutism, to unchanging dictates from God. In fact, religious conservatives exalt absolutism even when they fall far short of its standards. Caught in an adulterous affair in 2009, South Carolina Governor Mark Sanford apologized by reflexively acknowledging, “I’ve been a person of faith all my life. There are moral absolutes.”

For practical purposes in everyday life, the idea of moral absolutes can have understandable appeal. As we go about our business within a certain framework of place and time, there are actions and ideas that must be seen as good and evil, right and wrong. Politically, religious conservatives seize upon this need for certainty and exploit it for advantage, claiming that what seems certain in their lives today must be seen as eternally so, everywhere. This message can be powerful, especially in a society that is leaping forward technogically and thereby experiencing rapid social changes that many find troubling.

Nevertheless, since , slavery, forced marriages, and the oppression of women — just a few examples of concepts that were once considered moral — are no longer acceptable in civilized society, there is really no debate about whether morality evolves: It most certainly does! But religious conservatives nevertheless recognize that many feel threatened by change and find great comfort in tradition and absolutes, so they get much mileage from touting old-time (and often outdated) values.

Because of this, to argue against absolute morality in America can be political . In an environment where the media and the public will entertain nothing but sound bites and simplistic thinking, there is little interest in complex philosophical analysis of right and wrong. Traditional, absolutist moral rhetoric will usually go unquestioned, while news coverage instead focuses on other critical issues, like which candidate we’d want to have a beer with.

This is why Obama’s “evolved” view of same-sex marriage is not without risk: to succeed, he must convince the public that the idea of evolving morality is not sacrilege. And this is where we see the high cost of America's vilification of the secular demographic, which adamantly advocates for a naturalistic outlook that seriously and effectively challenges conservative religious moral absolutism.

To the extent the public accepts that morality was not dictated by God to ancient men, the progressive (and secular) position will prevail; but because seculars are too often considered political outcasts, you probably won't see Obama reaching out to the secular community for support on this issue. Instead, he looks for allies who happen to agree with him on the issue, without challenging the underlying assumptions of absolutism emanating from conservative circles. Clearly, visible inclusion of seculars in would introduce a vociferous opponent to the righteous religious absolutists, but nobody seems interested in welcoming them to the table.

Though a majority of Americans identify as at least marginally religious, the secular view of morality is hardly radical. After all, the most conservative Christian must concede that morality does change, that notions of right and wrong – even those that seem vitally important to the very fabric of society – will differ from place to place and from time to time.

In his book The Better Angels of Our Nature: Why Violence Has Declined, Steven Pinker points out that evolving notions of morality, often arising from the Enlightenment humanism of seventeenth and eighteenth century Europe, have been the catalyst for much of the civility and nonviolence that has become more prevalent in modern society. (If you think society is more violent now than ever, by the way, Pinker will prove you wrong.)

A few centuries ago, for example, typical Europeans would entertain themselves by torturing cats, public executions were festive events for the whole family, and wife beating, child beating, and racism were normal, hardly a sign of deep moral flaws. Even in modern America, until a generation ago, police would rarely intervene in matters of .

By understanding that a changing social and technological environment can justify a rethinking of moral standards – and that this does not necessarily shake society at its foundations – we allow ourselves to “evolve” into a more humane, free, and decent culture. Such an evolution may threaten conservative theology, but it is no threat to the rest of us.

David Niose’s forthcoming book, Nonbeliever Nation: The Rise of Secular Americans, can be preordered here.

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