Over the past three decades, American presidential elections have been dominated by a confessional political style where candidates must invoke God and quote Scripture in ways more testimonial, sectarian, partisan and liturgical than in previous elections.

As a result, campaigns often resemble a catechism test as our would-be leaders seek to find political salvation in the ballot box. One of the substantial problems of this confessional era is that entire groups of Americans are virtually ignored, or at least rendered second-class citizens, in the electoral process.

As candidates tailor their rhetoric with evangelical buzzwords and conversion experiences, they downplay or even ignore the religious experiences – or absence of such experiences – of other Americans, even though as president they must serve as leader of the entire nation.

Much as today’s confessional society has led to the exclusion of some candidates who cannot pass the ruling rhetorical religious test, it has also led to some American citizens assuming a diminished role in the electoral process.

For example, not only would it be impossible in today’s religious-political climate for a Muslim to mount a competitive bid for the presidency, but even Muslim citizens find themselves ignored by presidential candidates.

Barack Obama, whose own candidacy was plagued with false claims that he is a secret Muslim, has been accused himself by Muslims of avoiding public interaction with them. After two Muslim women in headscarves, both Obama supporters, were banned by Obama staffers from standing behind the candidate during a speech – and thus an image that would have been captured by TV coverage – Safiya Ghori, government relations director for the Muslim Public Affairs Council, stated, “The community feels betrayed.”

Although Obama frequently spoke in Christian churches and even some Jewish synagogues during the campaign, he did not appear once at a mosque. In fact, after U.S. Congressman Keith Ellison of Minnesota, the first Muslim elected to the U.S. Congress and a staunch Obama supporter, volunteered to speak at an Obama rally originally scheduled to be held at a mosque, the event was canceled by the Obama campaign because they wanted to avoid controversy.

Ghori said about the apparent political liability for candidates to appear with Muslims: “The joke within the national Muslim organizations … is that we should endorse the person we don’t want to win.” However, considering the democratic consequences of such exclusion from full participation in the electoral process, such a problem hardly seems like a joke.

Other groups of Americans have also been deemed “untouchables” in our confessional political era. For instance, much as being an atheist is the top factor that would lead American voters to not vote for a particular candidate, atheists in general are deemed untrustworthy by many Americans.

People excluded by our confessional politics are not just those citizens who hold religious beliefs other than Christianity or perhaps Judaism, but also other citizens who are viewed by evangelicals as transgressing their codes of “normality” or accepted beliefs and behaviors. One such group is homosexuals.

During the 2008 campaign, for example, Republican presidential hopefuls participated in numerous debates for special-interest audiences. However, every Republican candidate declined an invitation to appear at a forum focused on homosexual rights, although most Democratic presidential contenders attended.

Jack Majeske, past president of the Broward County Log Cabin Republican Club, argued that the Republican candidates skipped the debate because “[t]hey’re all afraid of the Christian right.” Just four years earlier, an important part of George W. Bush’s re-election strategy – and the election strategy of other Republicans – was pushing for state constitutional amendments banning same-sex marriage.

Even Democratic candidates sometimes seem willing to ignore the concerns of their homosexual supporters in a quest for religious voters. For instance, as Barack Obama targeted religious voters by holding gospel music concerts in South Carolina, one of the main musicians for the concerts was criticized for making anti-homosexual remarks.

The singer, Rev. Donnie McClurkin, claimed God delivered him from a homosexual lifestyle and called homosexuality a “curse.” Although Obama added a gay minister to the event – who had a much smaller role than McClurkin – many homosexual rights groups still condemned and protested the concerts. It seemed that for Obama’s campaign, winning religious voters – particularly African-Americans – was more important than repudiating someone considered hateful by a smaller part of the electorate. College of Charleston political science professor Jeri Cabot explained Obama’s rationale: “He can win without [the gay vote].”

With their sectarian rhetoric, our presidential candidates rhetorically exclude or even demonize segments of the American polity. Our presidential candidates rhetorically – and even literally – avoid Americans who do not fit the evangelical Christian standard that has been created in the confessional era. Thus, entire groups of Americans are prevented from full participation and having much influence in our nation’s political process.

Although all Americans are supposed to be treated equally as citizens, it seems clear that in a confessional era of politics, new classes of civic lepers have been created that – as in biblical times – must be avoided at all costs. With our evangelical and political leaders arguing that this is a Christian nation, such pronouncements inherently construct many Americans as not true or full American citizens.

It seems that for many evangelicals and presidential candidates, secularism has become the new communism that must be found and removed from all parts of our society. The exclusionary confessional discourse of our presidential candidates may help them win elections, but it harms the democratic ideals of equality and representation of all citizens.

Brian Kaylor is a contributing editor for EthicsDaily.com. This column was excerpted from his newly released book, “Presidential Campaign Rhetoric in an Age of Confessional Politics.”