Daniel Acker / Reuters

Were a Democrat from the Clinton, Bush, or Obama eras to watch the presidential-announcement video that Beto O’Rourke released on Thursday, they would likely be struck by how it ended. Or, more specifically, by how it didn’t end. O’Rourke did not close with any mention of God.

Until recently, farewells that invoke God were standard fare for Democratic and Republican candidates alike. Bill Clinton ended his 1992 convention speech with the words “God bless you, and God bless America.” At the 1996 convention, he declared, “God bless you, and good night.” Al Gore finished his 1999 presidential-announcement speech with the words “May God bless you. And God bless America.” John Kerry closed his presidential-announcement speech in 2003 by saying, “Thank you, and God bless you all.” Barack Obama ended his keynote address at the 2004 Democratic convention with the phrase “God bless you.” (Although Obama didn’t mention God at the end of his 2007 announcement speech, he began it with “Giving all praise and honor to God for bringing us here today.”) Hillary Clinton closed her announcement speech in 2015 with “God bless you. And may God bless America.”

O’Rourke exemplifies a new normal. None of the other major white progressive candidates—Bernie Sanders, Elizabeth Warren, or Kirsten Gillibrand—invoked God in their presidential announcements either. (Amy Klobuchar, who is running as a comparative moderate, did.)

Today’s white liberals don’t only talk about faith less than their predecessors did. They talk about it in a strikingly different way. Earlier Democrats invoked religion as a source of national unity. Bill Clinton declared in his 1992 convention speech, “There is no them; there’s only us. One nation, under God, indivisible, with liberty and justice for all.” In his 2004 convention keynote address, Obama famously announced, “We worship an awesome God in the blue states.” The implication was that religious observance was something Americans of both parties shared.

Today, by contrast, progressive white candidates more often cite religion as a source of division. In his announcement video, O’Rourke boasted that during his Senate campaign in Texas, “people allowed no difference, however great or however small, to stand between them and divide us. Whether it was religion or gender or geography or income, we put our labels and our differences aside.” The only reference to faith in Warren’s announcement speech was an acknowledgment that “we come from different backgrounds. Different religions.” The lone reference in Sanders’s was a call for “ending religious bigotry.” While white progressives once described religion as something that brought Americans together, they’re now more likely to describe it as something that drives them apart.

It’s not hard to understand why. For starters, the percentage of white Democrats who express no religious affiliation has skyrocketed. According to unpublished data tabulated for me last year by the Public Religion Research Institute (PRRI), 8 percent of white Democrats expressed no religious affiliation in 1990. By 2016, the figure was 33 percent. In 1990, white self-described liberals were 39 points more likely to describe themselves as Protestant than as religiously unaffiliated. By 2016, religiously unaffiliated beat Protestant by nine points.

Secular Democrats haven’t only grown more numerous. They’ve also become some of the party’s most motivated activists. As The Atlantic’s Emma Green has noted, a PRRI poll taken last August and September found that Democrats who shun organized religion were more than twice as likely to have attended a political rally in the previous year than Democrats who identify with a religious group. Today’s Democratic candidates cannot simply assert, as Obama did in 2004, that “we worship an awesome God in the blue states,” because so many active Democrats do not.

The other reason liberal candidates more often describe religion as a source of division is the rise of Islamophobia and anti-Semitism. Before Donald Trump, Republican religious discourse was more ecumenical. The 2000 Republican convention featured a Muslim prayer, and George W. Bush regularly spoke about Americans who attended a “church, synagogue, or mosque.” In such an environment, it was easier for Democrats to depict an America divided by race, class, and gender but unified by religious faith, even if different Americans expressed that faith in different ways. Today, by contrast, since more Americans don’t practice a religion, and the president demonizes some of those who do, it’s more natural to describe religion as a rift to be overcome.

But while there are legitimate reasons to talk about religion less (America has become a less religious country) and to describe it more negatively (religious bigotry has risen sharply), doing so could hurt Democrats such as O’Rourke in their efforts to defeat Trump. According to a 2016 Pew Research Center poll, while a small plurality of Democrats thinks politicians talk about religion too much, Republicans overwhelmingly think politicians talk about it too little. Among those Republicans are devout Christians who agree with Trump on abortion but consider him a detestable human being, and might be lured into voting against him by a Democrat who both spoke compellingly about a guiding faith and appeared to live by it.

Democratic candidates might be tempted to pursue an opposite strategy: employing secular rhetoric to rouse their secular base. But the Democratic base isn’t overwhelmingly secular; it’s partly secular and partly religious. Republicans, by contrast, are overwhelmingly religious. Which may explain why, according to a 2017 study in the Journal for the Scientific Study of Religion, candidates who were perceived as secular experienced a “drop in Republican support that … was not balanced by an increase in Democratic support.”

That’s partly because of African Americans. While many white Democrats want politicians to speak about religion less, black Democrats overwhelmingly want them to speak about it more. When asked in 2016 whether political leaders were talking about “their faith and prayer” too much or too little, black Protestants said “too little” by a larger margin than even Republicans. While only 41 percent of Democrats said it was very or somewhat important that a president shared their religious views, among black Protestants, the figure was 72 percent, again even higher than among Republicans.

All of which may help Kamala Harris and Cory Booker. It’s no coincidence that Harris ended her campaign-announcement speech with the words “God bless you, and God bless the United States of America,” and that Booker ended his speech at the 2016 Democratic convention by declaring, “God bless America.” In his campaign video, a bystander calls out, “2020!” To which Booker responds, “Amen!”

This religious language may reflect a genuine religious belief. But it also bespeaks a political reality: For Harris and Booker, whose path to the Democratic nomination requires winning the black vote, religious language is a necessity. And the same religious language that helps them win over African Americans in the primary may help them win over Republicans in the general election. In their appetite for public professions of faith, black Democrats and white Republicans are similar. It’s white liberals who stand out.

White progressives such as O’Rourke, Sanders, and Warren tacitly recognize that religion is no longer the force for national unity it once was. For Harris and Booker, the intriguing possibility is that it’s still unifying enough to propel them to the White House.

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