The Washington PostDemocracy Dies in Darkness

The political divide in the United States, animated

By itself, this gyrating beige lump doesn’t seem as though it tells us much about the state of American politics.

It’s an animation The Post created from images developed by Pew Research — and its initially unassuming appearance is deceiving.

Think of the start of the graph — the 1994 position — as being a bell curve in a high school class. The way a bell curve works, you may recall, is that it represents the distribution of grades. A few people fare very poorly on a test; they’re at one extreme. A few people do very well; they’re on the other. In between is everyone else, with the plurality of students forming a lump in the middle. When grading on a curve, those people get C’s, while the people at the far left get F’s and on the far right, A’s.

In this case, though, the far left is actually the far left. Or, more accurately, they are people who consistently hold liberal views on a number of subjects Pew asked about. The far right are those who most consistently hold conservative views. The lump in the middle? The big group of Americans who hold a little from each pot.

But then the image shifts. Over time, the bell flattens out until it’s barely a bell curve at all. It’s just an about-even distribution, with about as many F’s as C’s as A’s. Or, more accurately, with more people holding generally liberal views than conservative ones. (There are two reasons for the shift to the left, Pew notes: an increase in liberal views on gay rights and, perhaps unexpectedly, immigration.)

Part of the reason that the curve got flatter is that members of each party started heading to the poles.

According to Pew’s data, 95 percent of Republicans are more conservative than the median Democrat and 97 percent of Democrats are more liberal than the median Republican. Again, there are two factors to that: The median Democrat — meaning a Democrat for whom half of the party is more liberal and half more conservative — moved left at the same time that Republicans were moving right.

Those animations represent all of those who identify with one party or the other. Pew also broke out the charts based on how politically engaged the respondents were. “Political engagement,” Pew explained in 2014, “can take on many different forms, including voting, contributing money to a candidate or political group, working or volunteering for a campaign, attending a campaign event or contacting an elected official.”

If we consider only those Americans who take active steps to be involved in politics, the beige lump ends up misshapen in a slightly different way: Higher at the left side and higher on the center-right.

Comparing the two directly:

Why the movement at the edges? Because politically engaged partisans are much more polarized.

You may be surprised to see that the movement among more-fervent Democrats has been more extreme than among Republicans. You shouldn’t be. As we’ve noted, Democrats are consistently identifying as more liberal while Republicans are fairly consistent in their self-identification as conservatives — in part because Republicans had already moved significantly to that identification by the year 2000.

The natural question that arises from these animations is: What does this mean for American politics? Pew has completed regular analysis looking at how Republicans and Democrats are increasingly hostile toward and skeptical of those from across the aisle. More than half the members of each party view the other very unfavorably; in 1994, only about a fifth did.

The short answer to the question of what the flattening lump means, though, is this: Apparently we’re going to find out.