An American flag flies at half staff over the U.S. Capitol and behind the Peace Monument in Washington, D.C.Saul Loeb / Getty Images

The dim odds that Congress will respond to the Parkland school massacre with meaningful gun control and the flickering prospects it will pass immigration reform both reflect the same obstacle: the widening trench between the forces of transformation and restoration in American politics.

The convergence of the two policy debates today—with the nation reeling from Wednesday’s shooting in Florida and the Senate voting down an array of proposals on immigration—is coincidental but revealing. Both issues illuminate the central divide between the parties as their political coalitions have sorted and separated along lines of race, generation, education, and geography. On both matters, Republicans are championing primarily non-urban and predominantly white constituencies that want fewer immigrants and more access to guns. Democrats reflect a mirror-image consensus: Their voters coming from diverse urban areas usually support more immigrants and fewer guns.

The likelihood that Congress will ultimately stalemate on both issues—refusing to adopt any new restrictions on access to firearms and deadlocking over extending new protections to young people brought to the country illegally by their parents—is particularly striking given the overwhelming public support in polls for at least some action on both fronts. In polling last summer by the non-partisan Pew Research Center, 84 percent of adults said they supported background checks for all gun purchases (65 percent strongly), and 68 percent said they supported a ban on assault weapons (53 percent strongly).

Depending on the poll, up to about 85 percent of Americans say they support legal status for the so-called Dreamers, who have received temporary protection from deportation under former President Barack Obama’s Deferred Action for Childhood Arrivals program. And while three-fifths of Americans in an ABC/Washington Post poll last fall said they opposed building President Trump’s border wall with Mexico, nonetheless about two-thirds of respondents said they would accept a legislative deal coupling protection for the Dreamers with increased border-security spending. Support for such a deal was even greater among Republican-leaning voters than Democratic-leaning ones. Despite this public support for legislation on both issues, it appears likely that Congress will pass nothing.

The predictability of deadlock testifies to the power of the intertwined cultural, demographic, and economic divide now separating urban and non-urban America—and how closely the nation’s partisan split follows the contours of that larger separation. It also shows how population-distribution patterns that concentrate Democratic strength in the House of Representatives into the largest urban areas, combined with the small-state bias that accords each state two senators regardless of population, elevate rural over urban priorities in these polarized debates.

Republicans represent what I’ve called a “coalition of restoration” centered on the older, blue-collar, evangelical, and non-urban whites most uneasy about the tectonic cultural and economic forces reshaping American life. That means that compared with the nation overall, most Republicans are representing areas with more guns and fewer immigrants.

Forty-two of the 51 Republican senators, for instance, were elected from one of the 30 states where immigrants represent the smallest share of the population, according to Census data. Republicans hold just nine of the 40 Senate seats in the 20 states with the highest immigrant-population share. Likewise, 26 of the states Trump carried in 2016 were among the 30 lowest in immigration-population share; he won just four of the top 20.

Continuing the pattern, over four-fifths of House Republicans represent districts where the immigrant share of the population lags the national average. But, conversely, gun ownership is much more common among Republican-leaning constituencies and communities than in the nation overall. Pew last summer found that only about two-fifths of all Americans lived in a household with a gun in it; that result was similar to long-term Gallup polling and represents a measurable decline from the 1980s and early 1990s, when about half of households had a gun.

But at the same time, Pew found that nearly three-fifths of Republicans (and those who leaned toward the party) either owned a gun (44 percent) or lived in a house where someone else did (12 percent). Gun ownership was also higher than the national average among adults without a college degree, and especially elevated among those who lived in rural areas—two critical constituencies for the modern GOP. In the South, Midwest, and West—basically, everywhere outside the strongly Democratic-leaning Northeast—the percentage of rural households with a gun spiked to around 60 percent.

Across all of these measures, Democrats present an inverse picture. They now rely on a heavily urbanized “coalition of transformation”: minorities, Millennials, and college-educated and secular white voters, especially women. With that profile, the party is rooted in the places most touched by immigration. Sixteen of the 20 states Hillary Clinton carried in 2016 ranked in the top 20 for the highest share of immigrants. Thirty-one of the 49 Democratic senators, or nearly two-thirds, represent those 20 states. Nearly an identical percentage of House Democrats hold seats with a higher share of immigrants than the national average.

The gun divide is equally sharp. Just one-fifth of Democrats (and Democratic-leaners) said they owned a gun in the Pew survey; only another one in 10 lived in a house where someone else did. That’s roughly half the percentage among Republicans.

Only about one in four adults in two key Democratic constituencies, African Americans and those with a college degree or more, said they owned a gun. That number was about one in five for people living in cities and less than one in six for Hispanics—two other important constituency groups to Democrats.

Economic contrasts reinforce these cultural and demographic divides. Republicans dominate the states with higher per capita carbon emissions because they tend to be the places engaged in energy production and manufacturing; Democrats win most of the states with lower emissions because they tend to be the places, primarily along the coasts, that have transitioned furthest into the post-industrial information economy. Clinton, similarly, won 17 of the 20 states with the highest share of college graduates, while Trump won 27 of the 30 with the fewest.

The trends all track together. The interior states with few immigrants and more gun owners also tend to be more blue-collar, and more connected to manufacturing and the resource-extraction economy. The largely coastal states with many immigrants and fewer gun owners also tend to be more white-collar, and more connected to global markets and the digital economy. The contrasts are even more pointed when viewed at the metro and non-metro level within states.

With this hardening political divide, the few swing votes in Congress typically belong to the legislators caught, in effect, behind enemy lines: the Democrats representing mostly white, non-urban constituencies and the Republicans in diverse metro areas. That explains why West Virginia Democrat Joe Manchin was a leader in efforts to forge a bipartisan consensus on background checks for all gun sales after the Sandy Hook school shooting. It also explains why Arizona Republicans Jeff Flake and John McCain have been central to efforts to reach a bipartisan compromise on immigration in the past several weeks.

And yet in recent years, as the conflict between the coalitions of restoration and transformation has grown more intense, even most of those outlier legislators have been pulled toward their party’s side in this fight. In 2013, every Senate Democrat, even those from red states, voted for an immigration-reform bill that included a pathway to citizenship for 11 million undocumented immigrants. And on Thursday, most of the Senate Republicans from the 20 high-immigrant states—including Georgia’s David Perdue, Florida’s Marco Rubio, Nevada’s Dean Heller, and Texas’s Ted Cruz and John Cornyn—opposed the bipartisan compromise on immigration amid intense resistance to the plan from Trump and many conservative media voices.

On guns, the general pattern over the past 15 years has been that gun-control opponents have succeeded somewhat more than gun-control advocates in pressuring the legislators behind enemy lines to cross over. When Congress last year voted to overturn an Obama regulation making it tougher for people with mental illness to obtain guns through the national background-check system, virtually all of the House Republicans from metropolitan areas sided with gun-control opponents to back the repeal. (That included many of the Republicans from blue-state metro areas who top the Democratic target list in 2018, such as Steve Knight and Mimi Walters near Los Angeles, Barbara Comstock in Northern Virginia, Leonard Lance in New Jersey, Carlos Curbelo in Miami, and Ryan Costello and Brian Fitzpatrick outside of Philadelphia.) And while few House Democrats crossed party lines to support the repeal, it did win backing from five Senate Democrats facing reelection this year in states Trump carried (including Manchin).

The structure of congressional representation in both the House and Senate tilts the scales in these arguments toward rural interests, even as population growth tilts more emphatically toward urban centers. If you assigned half of every state’s population to each senator, the supporters of the 2013 background-check bill represented 194 million people, while the opponents, who were centered on sparsely populated Plains and Mountain states, represented only 118 million, according to my calculation at the time. But, using a filibuster, the opponents were able to block action. (The proposal would have faced uncertain prospects anyway in the House, which then, as now, was controlled by Republicans mostly representing non-urban areas.)

All the cultural and racial controversies raging through the Trump presidency increase the odds that the trench between the coalitions of restoration and transformation—metro and non-metro America—will deepen. The more attention that is drawn to explosive cultural fights on immigration, guns, and the like, the harder it becomes to survive for both red-state Democratic senators and Republican House members in blue metro areas. Many incumbents in each category could face a very difficult election this fall.

Both the immigration and gun-control debates flaring today capture two very different Americas living through divergent experiences and losing interest in compromising with each other. The best advice for voters may be to get used to that dynamic—because the social and political distance between these two Americas seems poised to only grow wider.

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