Is social media responsible for our democracy’s current crisis? An increasing amount of political information (and misinformation) gets disseminated online, and many Americans do not trust the media, do not trust Congress and do not trust the president. By many measures, voters are as polarized now as they have ever been in recent memory.
Many observers — even, before he left office, President Barack Obama — have tagged social media as a key driver of this crisis. The digital world offers no shortage of potential villains: targeted Russian ads; shadowy purveyors of fake news; political consultants like Cambridge Analytica wielding big data and cutting edge psychology; and formerly fringe media players like Breitbart leaping into the mainstream.
But we risk giving too much weight to the newest and most frightening media technologies. If any media platform is to blame, it is not the web. It is more likely television, which is a more important source of political information. Growing polarization may also result from structural economic changes, like rising inequality, that have occurred in recent decades.
A few facts can help keep the role of social media in perspective. The share of Americans who use social media as their primary source of political news and information is rising fast but remains relatively small. Recent work by Mr. Gentzkow and Hunt Allcott finds that only 14 percent of American adults reported that social media was their most important source of news for the 2016 election. On the other hand, 57 percent of American adults said that TV (cable, network or local) was their most important source.
It’s also important which demographic groups use social media. In a paper recently published in the Proceedings of the National Academy of Sciences, we show that polarization has been growing as fast or faster among elderly Americans — those least likely to use social media — as among those aged 18 to 39. This applies across a broader set of demographic groups: Polarization increased as fast or faster among the Americans least likely to use the internet compared with those who are most likely.
In the 2016 election, President Trump was most popular among demographic groups least likely to use social media. According to our calculations, Mr. Trump gained support relative to Mitt Romney among non-internet-using voters, but actually lost support among internet-using voters. An analysis by the media researchers Keith Hampton and Eszter Hargittai likewise finds that Hillary Clinton’s supporters were more likely to use Twitter and Reddit than Mr. Trump’s supporters.