Even before a left-wing mob laid siege to conservative commentator Tucker Carlson's house, the publication on Twitter of the home address of liberal journalist Matthew Yglesias, and the White House stripping CNN's Jim Acosta of his press credentials after he verbally sparred with the president, journalists were nervous that they had become targets in a politically polarized country. Heated rhetoric, threats, and violent attacks led many media outlets to step up security measures, and hundreds of news publications coordinated simultaneous editorials condemning President Donald Trump's criticism of the news media.

Journalists better get used to it. In a country divided between political factions that hate each other, most of the media have chosen sides. That makes them participants in, rather than observers of, the strife around us.

That America's political tribes hate each other is difficult to deny. "[I]f you're wondering why American democracy seems to have decayed so quickly, the graph below gives a big part of the story," social psychologist Jonathan Haidt tweeted in October, pointing to data from political scientists Marc Hetherington and Jonathan that shows growing domestic political animus. "When groups hate each other, they more easily believe that the ends justify the means," Haidt added.

In their book, Hetherington and Weiler point out that after 2000, "the percentage of partisans with hate in their hearts rose with each election: from the 20s and 30s for Democrats and Republicans in 2008, to 48 and 50 percent, respectively, in 2016. Clearly, hating the opposite political party is no longer a fringe thing."

Journalists have certainly not stayed aloof from the fray. Long accused of spinning their work to suit partisan and ideological preferences, media outlets in recent years have become more open about their leanings. Most have tilted to the left, while Fox News leads the small pack of outlets favoring the right (and with a few, such as Reason, wishing a pox on both their houses). That outbreak of honesty is probably a positive development, since it acknowledges a reality of which people were already aware. But, in a volatile and violent environment, it means that journalists have openly joined in political combat.

Some of the combat—like the long feud between CNN and Fox—is relatively harmless and even entertainingly popcorn-worthy. But Vox's Matthew Yglesias mused that he "cannot empathize with Tucker Carlson's wife at all" after she was terrorized by the attack on her home, and that his only objection was that the siege was "not tactically sound" (no word yet on the tactical wisdom of his own doxing). Maybe he was just following up on the suggestion of ThinkProgress justice editor Ian Millhiser that his co-ideologists "confront Republicans where they eat, where they sleep, and where they work" which, it turns out, is rather nastier in real life than in a tweet.

But neither Yglesias nor Millhiser have as prominent a pulpit as the blowhard in chief, Trump himself, who publicly characterizes the press as "the enemy of the American people" and "the opposition party" guilty of spreading "fake news" (it's often overlooked, but his predecessor took a similar view of the conservative press, calling Fox News "destructive" and illegitimate). Before the mid-term election, Trump praised Rep. Greg Gianforte (R-Mont.) who physically attacked Ben Jacobs, a reporter for The Guardian. That's more than troubling coming from an official who wields the vast power of the state.

The assault on Jacobs was high-profile, but not really isolated. "The field crews get the brunt of the public abuse—it's not just from one side," news photographer Lori Bentley-Law wrote in a blog post explaining her reasons for leaving her job, including widespread hostility and physical assaults. "We get it all the way around, pretty much on a daily basis."

"I don't need to tell you that we live in a political and ideological era that has become far more than acerbic; much more than toxic. It is now dangerous," writes Dan Shelley, executive director of the Radio Television Digital News Association.

This isn't the first time that American journalists have faced anger and peril while practicing their profession.

"Before the Civil War, running a newspaper could be pretty dangerous if an editor ran pieces against slavery," Becky Little wrote for the History Channel. "Basically, you had to accept that violence was part of the job."

"Slavery was a fundamental issue that needed to be resolved—I don't see anything quite as compelling as slavery in today's political environment," the University of Illinois's John Nerone, author of Violence Against the Press, told Little. "Nevertheless, when you have this kind of volatile political environment, you anticipate that there'll be a certain amount of violence."

Even short of violence, there's plenty of hostility for journalists in an era of rising populism and political polarization. Surveys of public attitudes in Europe find that "those who hold populist views value and trust the news media less, and they also give the media lower marks for coverage of major issues, such as immigration, the economy and crime," according to the Pew Research Center. Sure enough, a Knight Foundation/Gallup poll finds that "[m]ost U.S. adults, including more than nine in 10 Republicans, say they personally have lost trust in the news media."

Unsurprisingly, in these divided times, trust and distrust tend to be selective, with Republicans, in particular, favoring those few news outlets they consider to be in their corner. "Republicans who can name an accurate source overwhelmingly mention Fox News," notes Gallup.

That Democrats are less focused in their loyalties likely reflects the larger number of outlets that voice their views on political issues.

Which is where all of this begins: politics. Americans battle each other over politics in increasingly nasty and violent ways. Journalists are part of the society on which they report and have become participants in its tribal political battles.

"When Americans have less to fear no matter who wins political office, they'll be less prone to viciously fight each other for control of government," I've written about our political strife. Having joined the melee, journalists, like other Americans, will have an easier time of it only when government is rendered less dangerous and the struggle for power stops mattering so much.