The Daily Show and The Colbert Report were both responses to the Bush years. They were about the alienation liberals felt from their country at a moment when Fox News seemed the authentic expression of the American psyche and George W. Bush kept winning elections.

And then liberals began winning elections. The constant crises of Obama's early presidency gave the shows plenty to work with at first, but as the sirens quieted and Washington slowly froze into gridlock, the shows began to lose steam. The disappointments of the Obama administration didn't offer the comic fodder of the outrages of the Bush administration. Colbert and Stewart became the beloved voices of the dominant political coalition; punching Fox News was punching down. Colbert announced his move to CBS. Stewart announced his retirement.

Their replacements — Trevor Noah at The Daily Show and Larry Wilmore in Colbert's slot — are responses to the Obama era. Both are talented black comedians with a particular skill for limning America's complicated, and often infuriating, racial politics. Their work on The Daily Show focused on the racial controversies of the Obama era. And their takeover is a recognition of one of the lessons of Obama's presidency: American politics isn't moving past race. It's moving into it. And so, too, is the news business.

Obama's racialized presidency

The Obama era began amid the hope that American politics was finally moving beyond its old racial divisions. Five years later, something closer to the opposite has happened: partisan politics has cut new racial divisions into American life.

Consider this graph from Brown University political scientist Michael Tesler:

That is ... insane. There's a 42-point partisan gap on whether some racist oaf should be forced to sell the Clippers. There's a 38-point partisan gap on whether a searing film about slavery should win an Oscar. There's a 48-point gap on a Florida murder trial.

It wasn't always this way. In 1984, when Bernhard Goetz shot four young African-American men that he thought were going to mug him, there was no difference in the way Democrats and Republicans responded. Even the O. J. Simpson trial didn't lead to a large partisan cleavage:

But that was before Barack Obama was elected president.

Tesler's book Obama's Race: The 2008 Election and the Dream of a Post-Racial America describes an inconvenient truth of the 2008 election: it was the most racialized election in modern American history. There's been no recent campaign in which racial attitudes did as much to drive political behavior. And that's continued after the election.

Tesler worked with political scientist (and Obama's Race co-author) David Sears to test how racial attitudes — measured using a standard survey — drove the approval ratings of different presidents. The curve for Obama looks unlike anything else on the chart:

And all those numbers predate Ferguson, and Eric Garner, and #BlackLivesMatter. Attitudes toward race have long been a driving force in attitudes toward American politics. But in the Obama years, attitudes toward politics have begun driving attitudes toward race. The result is that racial controversies are a bigger part of American politics right now than they were before Obama's election.

Why the media suddenly cares about Ferguson

A central challenge of covering Washington right now is that barely anything gets done. The Senate can't even pass a bill to crack down on human trafficking. There's less happening, and readers (rightfully) care less about the little that is happening.

The opposite is true when it comes to what the internet has taken to calling "social justice" — roughly, the fights over racial, gender, and sexual discrimination, both overt and covert.

America is in the midst of wrenching demographic changes. Depending on which data set you believe, the percentage of US infants who were a racial or ethnic minority might already have tipped past 50 percent. In 2012, Obama won reelection with less than 40 percent of the white vote. The racial makeup of the country is changing, fast — and the force of that change can be felt in politics, and particularly in the political issues that young voters care about.

For the media, though, there's a force multiplier: the internet broadly — and social media specifically — increasingly dominates how people get their news (and that goes double for satirical news clips meant to go viral). And identity issues dominate online. If you ever wonder why there seems to be so much more coverage of identity politics these days, the answer, basically, is Facebook and Twitter, where stories that tap into people's identities dominate. BuzzFeed, perhaps the most successful publisher of the social-media age, demonstrates this particularly clearly: it's an identity-activation machine.

Some lament this trend, or at least its effects. My view is a bit more optimistic: for a long time, white men held the keys to the media, had relatively little data on which stories their audience actually cared about, and had little ability to find new audiences for stories that reached into new territory. So the media was heavily biased toward stories white men thought important, and toward audiences that were well-served by publications running stories white men thought important.

The internet has set off an explosion of media outlets, so more kinds of stories are being tried. There's a vast increase in reader data, so it's clearer which stories get read. And audiences now have the power to send stories viral, so there's more reward to writing about issues that affect people who may not already be part of your core audience. There are dark sides to the chase for viral traffic, of course, but on the whole, I think this is a pretty positive development in American journalism: it's helping us realize we were systematically giving too little attention to stories that weren't of interest to the kinds of people who dominated newsrooms.

But love it or hate it, it means stories that touch on people's core identities — and race, gender, and sexual orientation are about as core as identities get — are going to get a lot more coverage in the coming years.

A decade ago, a police shooting in Ferguson, or a religious freedom law in Indiana, might have been regional stories at best. Today, they become national stories with ease. Satirical news shows, by their nature, follow the news. As the news changes, they need to change, too.

This was the reality The Daily Show sensed when it brought Noah and Wilmore into the stable. And it's the future being bet on by making them hosts of their own shows. The Stewart-and-Colbert era was tuned for post-9/11 liberalism — and the post-9/11 media. The Noah-and-Wilmore era is tuned for post-Obama liberalism — and the post-social media.

Correction: Due to butterfingers, this article originally stated that Obama won reelection in 2012 with less than 30 percent of the white vote. It should have said 40 percent of the white vote, and now does.

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