I blame technology
I can't believe I haven't run across this Pew Research study before. It was released in June 2014, and it's probably the best explanation I've seen for how we've ended up in a situation where we may very well see a presidential contest between Donald Trump and Bernie Sanders.
What the study provides is solid data to demonstrate that the left and the right in this country have become so divided that they've all but stopped talking to one another. Not only have Democrats become more rigorously liberal and Republicans more rigorously conservative, but members of both parties have become certain that the other party is going to damage the country.
Some key numbers: In 1994, 16% of Democrats had a "very unfavorable" opinion of the Republican party, in 2014 that jumped to 38%. On the other side, 17% of 1994 Republicans had a "very unfavorable" opinion of the Democratic party, in 2014 that leaped to 43%. Perhaps even worse, 27% of Democrats in 2014 believed that Republican policies were a threat to the well-being of the country, and 36% of Republicans felt that way about the Democrats.
My guess is than in 2016 the numbers are worse than they were in 2014.
I see this regularly in my Google+ feed. I follow a number of left-leaning people who regularly excoriate Republicans as not just wrong about political goals and methods, but as a large group of stupid sheep following a small number of outright evil leaders, bent on enslaving the populace to enrich themselves. For one example, is a very intelligent and insightful man, and one who posts regularly about very interesting topics... but when the discussion moves to politics his foaming-at-the-mouth bombast is so one-sided and so hate-filled that I finally had to stop following him.
On the other side, most of my personal friends tend conservative, and my involvement in pro-gun discussion groups (e.g. I'm a moderator on the Guns across Google community) means I'm regularly exposed to conservative viewpoints. There I find liberals consistently ridiculed as a large group of stupid people following a small number of outright evil leaders, bent on enslaving the populace to gain power. Absolute, deep hatred of President Obama is common. To my conservative friends, Obama is not just the worst president in history, singlehandedly bent on destroying all that's good about the nation, he's almost an anti-christ. I find that particularly baffling given that he hasn't actually done much at all.
How is it that we've gotten to this point? As I said at the top, I blame technology, specifically our modern communications technologies and the way they allow us to seek out and live in echo chambers. President Obama said this well in his YouTube interview with Destin Sandlin ( ). He pointed out that media has become divided, with some people getting all of their information from Fox News and others going only to the New York Times, and that as a result they aren't even working from a common base of facts (note I'm not saying either news organization lies, but they both choose which facts they publish).
Even worse, online fora, and especially social media, have made it easier than ever for people to congregate only with like-minded folks. In Eli Pariser's 2011 book The Filter Bubble, he posited that Google's personalization of search results was going to result in this sort of effect, that Google would learn that conservatives only want to see conservative information and similar for liberals and that the search engine would only show them results that confirm what they already want to believe. I don't think this turned out to be true, partly because Google's personalization isn't that good, and partly because people at Google do think about these problems and have considered deliberately up-ranking alternative viewpoints.
But although it hasn't happened that way with Google search, it definitely has happened that online discourse has become increasingly siloed, even as it has become the primary way in which we hold political discussions. Social media is perhaps the most pernicious example, because it's subtle. If I choose to participate in, say, a Reddit pro-life forum, it's obvious I'm stepping into a bubble. But when I friend people whose comments resonate with me and un-friend those who don't (using Facebook terminology, though I don't use Facebook), it's much less obvious that I'm creating my own personalized echo chamber.
Essentially, online fora take our inbuilt psychological handicap, confirmation bias, the tendency to give more weight to information that supports our current beliefs and less to information that contradicts them, and gives it powerful technological assistance. Now, not only can our minds try to filter out what we disagree with, we can avoid hearing it at all. And there's a good deal of research that shows that when we embed ourselves in polarized online fora, we become far more extreme in our views and more antagonistic to opposing views.
If all of that weren't bad enough, the perception of anonymity and distance provided by online discourse makes it easy for people to be much more vicious than they would ever dream of being in person. Not everyone; some people behave just as nastily in real life as they do online, but those sorts get marginalized in real life, while online they lead the charge.
Destin's interview with President Obama highlights the difference. While Destin is a nice guy and not the sort who I think would ever be really vicious online, he disagrees with and probably disliked President Obama. But face to face he found himself able to make a human connection with the man. Granted that it didn't change Destin's political views, and granted that you don't get to be president of the United States without being a consummate politician, and that means being able to make people feel connected to you, but watching Destin's post-interview discussion, it's clear that he did achieve a greater ability to look at Obama's policies from his perspective. Understanding and civil discourse is how we progress, and those are much easier to do in person than on-line.
How do we fix this? Are we doomed to a vicious cycle of ever-increasing levels of polarization, becoming more and more mutually antagonistic? I sure hope not, but I don't see the way out. Technology can offer tools that enable us to find alternative viewpoints, but it can't make us want to.
It goes back to 1879 which, being only a decade after the Civil War had to also be a time of extreme polarization, and the 1879 levels correspond roughly to the 1980s.