MR. KOJO NNAMDIFrom WAMU 88.5 at American University in Washington, welcome to "The Kojo Nnamdi Show," connecting your neighborhood with the world. Later in the broadcast, Documerica, the story of a little-known project at the Environmental Protection Agency that captured photos of the sweeping changes that took place in the United States during the 1970s. But first, a familiar story about guns plays out on Capitol Hill.

MR. KOJO NNAMDIThe United States Senate on Wednesday put the brakes on a series of gun control measures crafted in response to the elementary school shootings that took place in Newtown, Conn. late last year. The defeated proposals included a plan to expand requirements for background checks for gun purchases even though polls indicate that roughly nine in 10 Americans support such an idea. But the politics of gun control remain as treacherous now as they ever were both at federal and local levels.

MR. KOJO NNAMDIJoining us to explore the dynamics at work yesterday in Washington and around the country is Quentin Kidd. He's a political science professor, chair of the Department of Government and director of the Watson Center for Public Policy at Christopher Newport University in Newport News, Va. Quentin is also the author of the book "The Rational Southerner: Black Mobilization, Republican Growth and the Partisan Transformation of the American South." He joins us by telephone. Quentin Kidd, welcome.

PROF. QUENTIN KIDDGood to be with you, Kojo.

NNAMDIA lot of people may be thinking to themselves today, Quentin, that the math does not seem to add up. According to polls, some 90 percent of Americans support expanding background checks for gun sales. Yet in the U.S. Senate yesterday, the idea couldn't even win the support of 60 percent of the chamber.

NNAMDIThe president laid blame on the influence of the National Rifle Association who he accused of willfully lying to members of Congress and to the American people. How would you explain the dynamics that were at work yesterday on the Hill? Most Americans think that if 90 percent of us support something, then that support, that majority should be somehow reflected in the Senate, but it wasn't yesterday.

KIDDWell, the math of public opinion is different than the math of Senate votes, Capitol Hill votes and the U.S. Senate. Let me explain it this way. In the last 20, 25 years, the National Rifle Association and other gun rights groups have been very effective in energizing voters who do feel strongly about gun control. And those on the other side of the aisle, organizations on the other side of the aisle have not done the opposite of that for their supporters.

KIDDThey haven't mobilized their supporters in support of stricter gun control legislation. And so when senators go to vote and they're from a state like Montana or Alaska or North Dakota, they have to ask themselves: Am I going to run for re-election and be confronted by an organization that will mobilize voters who feel very passionate about this? And then not be supported on the other side by organizations that are mobilizing voters to support me.

KIDDAnd I think a lot of them, like, you know, Mary Heitkamp, Max Baucus, you know, Mark Begich, they say, look, I just can't run that risk. So I think there's a real challenge with the organization Mayors Against Illegal Guns. Are they going to become the counterpoint to the NRA? And I think there are enough senators that aren't sure of that yet. They're not willing to take that step.

NNAMDIThe suggestion you're making, the point you're making is that the people who are opposed to background checks may be in the minority, but they tend to be more passionate than the people who favor background checks. And they also tend to be more politically active, especially through the National Rifle Association and other pro-gun organizations come election time.

KIDDYeah. That's right. I mean I think there are some -- there are what we know as single-issue voters, people who feel strongly about abortion, people who feel strongly about gay rights, for example, issues around prayer. I think there are single-issue Second Amendment voters as well, and they think of any kind of restriction on gun rights in the same way, and they feel passionate about it, and they'll vote about it.

KIDDYou know, polls show overwhelming support for cracking, you know, for restricting gun rights, for example, for restricting sizes of magazines and that sort of stuff, background checks and that sort of stuff. But the vast majority of those people who support it don't vote on it. They support it because it seems to make sense to them, but they don't feel passionate about it, and people who oppose it feel passionately about it. And so senators know that.

NNAMDII've got one indication of that already, Quentin Kidd. We haven't given out the phone number as yet, and we already have a call from a person who is apparently opposed to background checks. So that's an indication of the passion that you're talking about. By the way, the number is 800-433-8850. But George in Richmond, Va. has already called it. George, you're on the air. Go ahead, please.

GEORGEGood afternoon. Yeah. I don't have a problem with, you know, say, gun -- I don't want -- like to use the term gun control because that smacks of tyranny, OK? But the other issue is everybody is tap-dancing around the real issue. The real issue is you need to focus on whether they're garden-variety criminals, whether they're, you know, gang members or whether they're just your average psycho.

GEORGEThe weapons used aren't really the issue, OK? I know, you know, literally, thousands of people that are gun enthusiasts. Some have guns, one, two. I personally have almost 30. But, you know, I'm not going to go use it like what we're referring to here. It's just like saying let's outlaw the corvettes on the highway because of the people who get caught speeding in sports cars. You know, you address the individuals who break the law by speeding.

GEORGEYou don't outlaw corvettes. You don't outlaw Mustangs. You see what we're getting at here? And the problem is the average person, even people that I know that don't really aren't into guns, they don't trust the government just like I don't, just like up here in D.C., when they had the gun restrictions up there. Yeah. You can own one, but it's got to be disassembled. Ammunition has got to be separate from the gun. Yada, yada, yada, yada. Well, that is de facto gun elimination, and that's what people are really worried about, me included.

NNAMDIGeorge, thank you very much for your call. Quentin Kidd, that's passion, isn't it?

KIDDThat's passion, and that passion is exhibited by a not small but not large but a sizable number of Americans who will vote on it, who will...

NNAMDIBut George is calling from Richmond, which is a big city. But do you have a sense right now for the way this issue may divide urban communities from rural ones in general?

KIDDYeah. I think what -- part of what's going on here is we've got states with political cultures that are influenced by their larger urban areas or their growing urban areas and states with political cultures that are influenced by their rural -- that culture and their rural background. And I think, you know, senators who come from states who have a more rural political culture feel more at risk voting for this. You know, I'm thinking of Mark Pryor from Arizona, for example, who voted against it, Harry Reid from Nevada who voted against it.

NNAMDIWell, Harry Reid, from Nevada, said he voted against it because of a rule, a process that will allow him to reintroduce the measure since he, of course, is the Senate majority leader.

KIDDRight. Well, and others. Mary Heitkamp from North Dakota...

NNAMDISure.

KIDD...who, you know, Max Baucus, for example, these are states with rural political cultures who have to go back and explain to their rural constituencies why they voted for it. Take Maryland and Virginia...

NNAMDII wanted to talk about Virginia for a second because you conducted a poll at Christopher Newport earlier this year that found the vast majority of Virginia supported closing the loophole that allows for people to buy guns at gun shows without passing background checks. But if anything, the politics of gun control have moved in the opposite direction in recent legislative sessions in Richmond. How would you compare what you've studied in Virginia to what's being taking place at the national level? And then I'm going to get to Maryland.

KIDDIn Virginia -- OK, in Virginia, we've got a changing political culture. We've got an increasingly urban state and suburb state that is confronting a historically rural political culture. And that historically rural political culture still has power, although every redistricting cycle it shifts more towards the urban-suburban parts of the state. And I think that really is what's going on in Virginia.

KIDDWe see change over the last couple of decades in Virginia in where people are moving, where they are living, where they live. The issues are, you know, if they live in an urban or a suburban area, the issues they're concerned about are different than if they live in a rural area. People have been moving away from the rural areas to the urban areas. But the -- but state legislative politics haven't caught up with that. And I think that's really what's going on in Virginia.

NNAMDIWhy are the politics on this issue so different in Virginia as compared to Maryland where the General Assembly just passed a law that banned high-capacity magazines, that expands the state's licensing program to include fingerprinting? I think you were about to talk about that anyway.

KIDDRight. And polling in Maryland shows strong support for all that. I think it is the political culture of Maryland that is more influenced by the Washington-Baltimore metropolitan area. The concerns in a metropolitan area are more towards safety, more towards services. And I think that kind of political culture is one where people are more willing to accept limitations on things like the ability to buy a gun because they recognize the importance of safety.

KIDDI mean, the fact of the matter is, when you live close to other people, there are issues that become more important to you about safety than when you live far away for other people. And I think it's a political culture difference. The political culture of Maryland is slightly different from Virginia, but I think Virginia's political culture is moving in that direction as Virginia becomes more urban and suburban.

NNAMDIOn to the telephones. Here is Celwin (sp?) in College Park, Md. Celwin, you're on the air. Go ahead, please.

CELWINHi. Thanks for taking my call. I've listened to a lot of discussions about gun control issues. And what is not being said is that nobody is saying we're going to take guns -- the government is going to take guns away. Nobody is saying you can't go and buy a gun, or you should not own a gun. What they're saying is gun control, to me, means, when I go to buy a gun, somebody is going to run a background check to determine that I'm not an ex-felon or a severely mentally ill person that is -- and it has been documented that I should not own a weapon.

CELWIN'Cause I lived in Richmond, Va. for a while. I bought a gun, and I had to go through a background check. And I went, and I got the training that was necessary to a carry a weapon, a concealed weapon. I thought that made a lot of sense. So why are people so afraid of gun control when all it's doing is giving you a background check?

NNAMDIWell, it is not that simple are people simply afraid of a background check. As Quentin Kidd has been explaining, the politics go both wider and deeper than that. Maybe this can help to explain it, Quentin, one man who was in the hot seat in Washington this week was Sen. Mark Warner, who's up for re-election next year.

NNAMDIHe has long enjoyed a good rating from the NRA. But since the Newtown shootings, he said he changed his perspective on the issue. He voted in favor of the background check measure yesterday. What do you think -- and maybe this will help to explain to Celwin. What do you think is at stake politically for Mark Warner on this issue?

KIDDI think Mark Warner realizes that he has trust. I mean he has one of the most valuable things that an elected official can have, and that is the trust of voters in his state. And I think he realizes that he can go back to those voters and say, here's what I was trying to accomplish. And Virginia happens to be a state that had a gun-related tragedy at Virginia Tech.

NNAMDICorrect.

KIDDAnd I think you can go back to voters and say, I'm not going after gun rights. I'm trying to make it harder for certain people to buy guns. And he's got the trust of voters in Virginia. Poll after poll shows that. And I think he was essentially cashing in on some of that trust.

NNAMDIAnd maybe that's what the other senator for Virginia, Tim Kaine, also did yesterday. He also voted in favor of the measure. Tim Kaine, by the way, is going to be our guest on The Politics Hour tomorrow at noon. And for those of you who called in wanting to participate in this gun control conversation, you should know that at one o'clock, it's going to be your turn. So you may want to call in then at 800-433-8850 'cause that's one of the topics we think you'll be wanting to discuss. But thank you very much, Celwin, for your call. And, Quentin Kidd, thank you so much for joining us.

KIDDTake care, Kojo.

NNAMDIQuentin Kidd is a political science professor, the chair of the Department of Government and the director of the Wason Center for Public Policy at Christopher Newport University in Newport News, Va. We're going to take a short break. When we come back, Documerica, the story of a little-known project at the Environmental Protection Agency. It captured photos of the sweeping changes that took place in the U.S. during the 1970s. I'm Kojo Nnamdi.