The media increasingly lament a “divided” and ever-more “partisan” nation, with television news mentions of such words surging since the election of Donald Trump. Yet beneath these overt references to a national divide lies a less obvious indicator of how far our divisions have come: the use of “us” and “them” pronouns. Do media outlets consistently use words like “us” and “we,” grouping the audience in with themselves? Or do they favor “they” and “them” to refer to “others”? It turns out President Obama’s second term marked a turning point in this regard, while the Mueller report was the moment that truly fractured the press into distinct partisan camps. The “Mueller moment” is visible even on Twitter.

Are we a more “divided” nation? The timeline below shows the percentage of airtime on CNN, MSNBC and Fox News by year since 2009 mentioning “divisive” or “divisions” or “divided” using data from the Internet Archive’s Television News Archive processed by the GDELT Project. (Click on the graph to enlarge.)

From 2011 to 2014 the terms surged in usage on MSNBC, while CNN and Fox News saw little change other than a slight increase in 2012. All three news channels sharply increased their mentions of divisions in 2016 with the campaign season and election of Donald Trump, though mentions on MSNBC were not that much higher than they were in 2012 and 2013.

Similarly, mentions of “partisan” or “partisanship” are much higher on MSNBC during Obama’s second term compared with CNN and Fox. However, while “divisive” peaked in 2016, that actually marked the lowest number of mentions of “partisanship” on the three news outlets. Instead, it was the following three years, after Trump became president, that mentions reached their highest levels.

Such divisions can also be expressed in terms of the more subtle selection of pronouns. Media coverage might use more “in-group” pronouns such as “us” or “we” or “our” or “ours” to refer to the audience as part of their group, or “out-group” pronouns such as “they” or “them” or “their” or “theirs” to invoke the concept of “other.” (These eight words are not exhaustive but capture a cross-section of such language.)

The timeline below shows the percentage of all words spoken on CNN that were either “in-group” terms or “out-group” terms by month since July 2009.

Usage of both sets of pronouns has steadily declined over the past decade, but from the middle of 2013 through the end of 2015 mentions of out-group terms surged to become almost equal with in-group terms. A similar phenomenon is observed in both MSNBC’s and Fox News’ coverage.

The mid-2013 start date marks the point when mentions of “divisions” sharply increased on MSNBC. It also coincides with the end of elevated mentions of “economy” and “economics” on the three channels, as their recession coverage came to an end around the time that out-group mentions began increasing.

The timeline below plots the difference between the two (in-group minus out-group) for the three channels using a six-month rolling average to smooth the data to make the trends more apparent.

From early 2013 through the mid-2015, mentions of out-group words steadily increased across all three channels, then rapidly ramped down as the presidential race kicked into high gear later that year, suggesting campaigning focused more on “us” than “them.” Trump’s election marks the point where the two sets of terms reached their greatest divide of the past decade.

Yet perhaps the most telling part of the graph above is the period beginning in April 2019. Other than a brief period in 2009-2010, all three channels have exhibited very similar behavior over the past decade. The release of the Mueller report in April upended this period of stability. In the months since the report’s release, MSNBC has trended more and more toward in-group language, Fox News has rapidly favored out-group wording and CNN has largely remained in the middle of the two.

In short, the Mueller report’s release marked a moment unseen in the past decade: an existential division among the three channels over whether to favor “us” or “them.”

What about social media? The timeline below shows the percentage of all English-language tweets that contained the in-group or out-group words, from January 2012 through September 2019.

Here the picture is slightly different, with in-group language remaining largely stable through the beginning of 2016, while out-group language steadily decreased. Around February 2016, both sets of pronouns begin steadily increasing, with a sharp increase from August 2017 through February 2018.

The timeline below shows the difference of the two groups (in-group minus out-group), revealing that over the past seven years Twitter has trended steadily towards “us” language over “them” language.

One limitation of this graph is that an increasing percentage of tweets are retweets, meaning the graph above reflects both original tweets and those that have been widely shared.

The graph below shows the same timeline with retweets eliminated, and thus features only original tweets. This graph lacks the steady upward progression of the all-tweets graph. This suggests that the tweets that go viral on Twitter are increasingly those that address the reader as “us” rather than speak of a distant “them.”

In contrast, with the removal of retweets, the timeline begins to look more similar to that of television news, with a steady shift toward out-group language from late 2013 through early 2016, followed by a shift back toward in-group language through the election. Over 2018, there again was a steady shift toward in-group language, reaching a peak in November 2018 with the midterm elections.

Mirroring the trend seen in television news, a marked shift toward out-group language begins in the days after the Mueller report’s release. Though in the case of Twitter, the trend reversed as of the last week of August and continued through the end of September.

Putting this all together, whether measured by explicit mentions of “divisions” and “partisanship” or the more subtle change in “us” versus “them” pronouns, the media are increasingly painting a portrait of a divided nation. The release of the Mueller report appears to have been a watershed moment that split partisan fractures wide open as measured by both media and social media.

RealClear Media Fellow Kalev Leetaru is a senior fellow at the George Washington University Center for Cyber & Homeland Security. His past roles include fellow in residence at Georgetown University’s Edmund A. Walsh School of Foreign Service and member of the World Economic Forum’s Global Agenda Council on the Future of Government.