STEVE INSKEEP, HOST:
The political map of America changes, but it doesn't change very quickly. Massachusetts was a reliably liberal state decades ago and still is. The South is still the South. This raises the question of why it is that certain areas come to be reliably liberal or conservative.
NPR Shankar Vedantam joins us to discuss some research that explores the question. Hi, Shankar.
SHANKAR VEDANTAM, BYLINE: Hi, Steve.
INSKEEP: What's the research?
VEDANTAM: Well, Barack Obama told us in 2004, Steve, that there were those red states and blue states, there were only the United States. Even he now says that was only an aspirational idea.
INSKEEP: Yeah, PolitiFact did not grade that went very well.
INSKEEP: But go ahead.
VEDANTAM: So the question is why do we see this clustering. If the country as a whole is fairly evenly divided political, why do we see these concentrations of red and blue? Now, one theory is that it's because of feedback effects. If you live in an area that is conservative to begin with, over time, you become conservative yourself. So that's...
INSKEEP: You hear lots of conservative views around you, in other words.
VEDANTAM: Exactly, so that's the theory suggest that geography shapes your ideology. There's new research now that links the red state/blue state phenomenon with the fact that 40 to 50 million Americans move every year. So we are an increasingly mobile society. I spoke with psychologist Brian Nosek at the University of Virginia. He's been tracking more than a million Americans and they revealed two things about themselves: one, their political orientation and two, their zip code.
Here he is.
BRIAN NOSEK: What we found is that people's current zip code was more aligned with their ideology than their past one. So, liberals who had lived in more conservative districts were more likely to now live in more liberal zip codes, and vice versa for conservatives.
VEDANTAM: So basically, what the data is suggesting, Steve, is when liberals find themselves in a conservative zip code, they're more likely to get up and move. When conservatives find themselves in a predominantly liberal area, they're likely to do the same.
INSKEEP: OK. This is really interesting because the question is how is it when Americans move so much that we don't just end up with a giant salad, with a giant mix where things are ideologically very similar from place to place. And it's because people, by choice or otherwise, are moving to live closer to people more like themselves.
VEDANTAM: Yeah. And it's probably one factor among many. You know, people are also moving based on where the jobs are. They're moving based on where their families are. If you have a job and a family that you love in a particular place, you're probably not going to uproot everything and move. But if you feel like there's a poor fit in there's an opportunity that comes up in another state where you feel like there's a better political fit, you probably are going to take the opportunity.
INSKEEP: But let's talk about that for a moment. This is not a new idea. There was a book called "The Big Sort" by Bill Bishop that explored it some years ago. The idea was that people were somehow deliberately, or nearly deliberately, sorting themselves ideologically. But does this research prove that that is why people are moving to live among people who are politically similar to themselves?
VEDANTAM: Well, Nosek and his colleagues tried to figure out if there was an experimental way to test this. And it's very tricky to test this experimentally, Steve, because when someone moves, is it because of their ideology or is it because of something else?
VEDANTAM: So a Ph.D. student who is working with Brian Nosek, Matt Motyl; he devised this interesting experiment. He manipulated people's ideology to see what effect it had on their desire to pick up and move. He gave people a questionnaire that was designed to trick them into feeling either more liberal or more conservative than they really were.
VEDANTAM: So he asked people, for example: Do you think abortion should be legal under all circumstances? Now most Americans don't think abortion should be legal under all circumstances. But answering no to that question made volunteers feel more conservative than they might've been.
INSKEEP: Oh, even if you're pro-choice and you feel like you're a liberal, by stating this really, really far out liberal position, you feel kind of conservative by comparison.
VEDANTAM: Exactly right. Now if you also ask other people: Do you think abortion should never be legal? Most Americans don't believe that either. But answering no to that question made people feel more liberal than they may have been.
He then gauged how moving people's ideology, what effect this had on their willingness to move, and he found that when people sense that they were living among the enemy - so to say - they had a greater desire to pick up and leave.
INSKEEP: So in other words, this research suggests that your ideology, when you compare it with your neighbors, actually will influence you to move or it may be one of the factors that influences you to move.
VEDANTAM: It might be one of the factors. And, you know, I asked Nosek whether he thought this was a good idea or a bad idea, and the interesting thing was he said it might be both. Here's the positive side.
NOSEK: If I am in a place where I feel like I belong, where people are like me, then there's good evidence that my health outcomes will be better, that I will get along better with other people, that I will actually perform better on tasks because I'm feeling like this is a community where I fit in, I feel like I'm part of the community.
INSKEEP: So OK, political polarization is good for you. That's the finding there.
VEDANTAM: Well, I mean so there is the downside. The downside is that if this mobility phenomenon is real, it means that the more mobile we get as a society, the more polarized we're going to become. Red states are going to get redder. Blue states are going to get bluer. The United States is going to get less united.
INSKEEP: Shankar, thanks very much.
VEDANTAM: Thank you, Steve.
INSKEEP: NPR's Shankar Vedantam. You can follow him on Twitter @HiddenBrain. You can follow this program at MORNING EDITION and @nprinskeep.
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