'Hope' is out, 'fight' is in: Does tweeting divide Congress, or simply echo its divisions?

Note: The National Press Foundation honored USA TODAY data journalist Aleszu Bajak and visual designer Ramon Padilla with the 2022 Innovative Storytelling Award for this analysis. Our work is not possible without readers like you. Thank you for supporting our journalism.

A short decade ago, Congress Twitter was gilded with collegiality, well-wishing and civil debate.

Arizona Republican Sen. John McCain in 2011 thanked Senate Majority Leader Harry Reid, Democrat of Nevada, for his “kind words” following a floor speech. For that year's state of the union, Rep. John Lewis, Democrat of Georgia, tweeted that he was “very pleased to be sitting with my friend and colleague” Rep. Tom Price, Republican of Georgia.

McCain recommended a book by Sen. Joe Lieberman, Independent of Connecticut. Sen. Tom Harkin, Democrat of Iowa, congratulated Republican Sen. Chuck Grassley in a 2012 tweet for his long tenure in Congress.

Oh, how times have changed.

Although many Americans sense the nation's lawmakers have become increasingly polarized in the past 10 years, a new USA TODAY language analysis of 2.8 million congressional tweets illustrates just how dramatically this particular form of public discourse has shifted, in tone and in substance, since 2011.

Early congressional adopters of Twitter in both parties commonly used phrases like “read,” “benefits” and “hope.” By 2021, Democrats were more apt to use words such as “victim,” ”condemning” and “firearms.” Republicans were more often saying “communist,” “bureaucrats” and “woke.”

The data show lawmakers segregating into distinct rhetorical clusters linked by party, effectively speaking different languages. And both parties grew more emotional in their choice of words through the implementation of Obamacare, government shutdowns, two impeachments and the overturning of Roe v. Wade.

An unanswered question: Did the decline of common ground on Twitter reflect a fundamental change in attitude among lawmakers, or did the rise of Twitter itself accelerate the breakdown — by encouraging more and more pithy attacks? Either way, experts say the outcome is not healthy.

Libby Hemphill, a professor at the University of Michigan who studies political communication, said the analysis underscores how parties are increasingly talking about different issues, “which means what’s important to one side isn’t important to the other. It means we can’t agree on what we should talk about.”

That has consequences beyond posturing on social media, said Hemphill. “Polarized parties don’t make good legislation. That’s why it matters.”

Equally troubling is that this type of language from politicians “tends to drive mass polarization rather than vice versa,” said Yphtach Lelkes, a political scientist at the University of Pennsylvania. “It makes people see the world as much more polarized and treacherous than it actually is, which then is self-fulfilling.”

Here's how Congress has become more linguistically polarized since 2011:

The shift in alignment over a decade is measurable.

USA TODAY's analysis sorted lawmakers into clusters based on similarity of language. Back in 2011, membership in each of the largest linguistic clusters was about evenly balanced between Democrats and Republicans. Starting in 2015, all of the major clusters were heavily tilted toward either Democratic members or Republican members. Only a handful of mixed clusters remained, and they tended to have the fewest members.

Strung together in rapid succession -- as we've done with the animation below -- the impact of changes in language on Twitter is clear. With the passage of time, Republican and Democratic members of Congress increasingly have isolated themselves into separate partisan camps.

More emotion. More fighting words.

While the language Congress uses on social media has become more linguistically divergent, its tone has also evolved. Using a list of polarizing words developed by researchers who study political speech, USA TODAY mapped the tenor of Congressional tweets over time.

The analysis shows that over the last decade there has been an uptick in the use of more emotion-grabbing language by Congress on Twitter, characterized by the increased use of words such as “violence,” “crime,” “worse,” “blame,” “wrong,” “threat,” “destroy,” “enemy,” “corrupt” and “scheme” as a share of all words.

USA TODAY's analysis found a major rise in polarizing language from Democrats that started just before Donald Trump's election in 2016 and a steady increase from Republican members since 2018.

To be sure, these words are a small share of all words tweeted by legislators but the change is noteworthy. These findings are in line with work by Andy Ballard, a professor at American University, who published a 2022 study of Congressional tweets pinpointing a jump in polarizing language from Democrats following Trump’s election.

Increase in emotional language in congressional tweets

Since 2011, there has been an uptick in polarizing, emotional language from members of Congress on Twitter, characterized by the use of words such as “violence,” “crime,” “worse,” “blame,” “wrong,” “threat,” “destroy,” “enemy,” “corrupt” and “scheme” as a share of all words.

USA TODAY's analysis is in sync with the findings of other researchers who have studied the evolution of congressional social media posts. It also lines up with findings based on other types of political speech and action by members of Congress.

There is research examining how Congress votes on bills and other measures of cooperation showing an increase in polarization over time and a 2015 study using roll call voting found that “partisanship has been increasing exponentially for over 60 years.” A 2019 study measuring polarization using speeches from the congressional record found that partisanship of language "has exploded in recent decades."

Annelise Russell, a professor at the University of Kentucky, has found negative tweets from Congress – posts attacking or blaming the opposing party – have increased over time. “You had Republicans sounding the charge during the Obama presidency, but then Democrats got even more negative during Trump,” said Russell.

Congress is using 'fight' more and 'hope' less on Twitter

This increasing polarization of Congress, both rhetorically and legislatively, is reflective of how Americans have increasingly sorted themselves politically and hold unfavorable views of the opposing party.

A 2014 Pew Research Center study found that Democrat and Republican voters are more ideologically divided than in the past. Last month, Pew published another report finding partisan hostility has only grown in the years since.

This so-called “affective polarization,” the tendency to dislike and distrust the other party, is growing, according to research by Lelkes and others. Polarization, experts say, has important consequences for the health of democratic systems.

Republicans are increasingly sharing politically biased news articles on Twitter

News domains shared by GOP members of Congress on Twitter are increasingly right-leaning, according to ratings assigned by Media Bias/Fact Check based on a media outlet’s political bias. Foxnews.com has a rating of +2, MSNBC.com has a rating of -2 and C-SPAN.org has a rating of 0.

Twitter and the state of partisan language in Congress

Do angry tweets reflect an angry Congress, or did Twitter make Congress an angrier place?

Experts told USA TODAY there are several forces at play in political social media. While politicians increasingly tend to take more extreme positions, Twitter has also evolved to incentivize more extreme positions because those receive more engagement from users.

A quick read of congressional tweets shows that a decade ago, the social media platform acted more like a real-time press release for legislators. The language was more formal, more civil and more administrative. In 2011, only one-third of Congress was posting on official Twitter accounts. Over time, the platform has evolved, in volume but also in tone.

Today, a majority of congressional Twitter accounts post nearly every day. Posts with the most provocative, emotionally-charged messages tend to accumulate more likes and retweets – metrics many of the people who manage congressional Twitter accounts undoubtedly track. This, in turn, incentivizes members of Congress to take increasingly extreme positions on Twitter.

“Twitter is a space where conflict entrepreneurs thrive,” said Dominik Stecula, a professor of political science at Colorado State University. “This is a space where you're test-driving different talking points and trying to go viral. That seems to be the primary motivation. It's not about service to your constituents.”

Which makes it difficult to tease apart how much the platform or the politicians are to blame for driving polarization. While American political speech has become less civil and more polarized, “there’s an aspect of human psychology that is beyond the moment,” said Ballard, the American University professor.

“Emotional appeals work,” said Ballard, and in Twitter politicians have found “a good venue for certain types of emotional language.”

And it's likely that the growth of this polarizing political rhetoric will not soon be reversed.

“Anger and resentment have been powerful tools for politicians for a long time, and social media is especially useful for whipping up emotions,” said Hemphill, of the University of Michigan.

The trend may “also be related to wider adoption,” she said. “There just weren't that many members of Congress using social media in novel ways 10 years ago, and now they're basically all invested.”

Aleszu Bajak is a senior data reporter on USA TODAY's investigations team. He can be reached on Signal at 646-543-3017 or by email at abajak@usatoday.com.

USA TODAY used a technique known as agglomerative hierarchical clustering to categorize tweets by their linguistic similarity. The analysis includes all words appearing more than five times in tweets from the official accounts of members of the 112th through 117th Congresses tweeting during those two-year periods. Two Independents who caucus with Democrats are colored blue in cluster visualizations and omitted from further analysis. Twitter text content is courtesy of ProPublica, and news article URLs are from Technical University of Graz, Austria. A list of official congressional Twitter accounts came from Ballard et al.'s 2022 study "Dynamics of Polarizing Rhetoric in Congressional Tweets." Emotional lexicon is from Simchon et al.'s 2022 study "Troll and divide: the language of online polarization." Code for this analysis can be found on GitHub.

This analysis was informed by the reporter's Summer 2022 fellowship at the Complexity Science Hub Vienna.

This article originally appeared on USA TODAY: How Democrats and Republicans in Congress splintered on Twitter