The evening of Tuesday, Nov. 6, brought the latest visual manifestation of our highly divided country: the 2018 midterm elections map. The map was similar to previous election maps — blue on the coasts and, across the rest of the country, wide swaths of red interrupted by blue dots. The major change was in the size of those blue dots: Increasingly, they seemed to be composed of both large cities and the suburbs that surround them. But why?

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For two years, the main analytical lens for explaining the unshakable red-blue division in American politics has been culture and ideology: Fox News vs. MSNBC. Gun owners vs. gun skeptics. Colin Kaepernick detractors vs. Colin Kaepernick supporters. “How Everything Became the Culture War” read one recent headline in Politico Magazine. And on the surface, the 2018 midterm elections did indeed appear to boil down to cultural issues: the approach of a caravan of Honduran migrants; the rival narratives of Brett Kavanaugh and Christine Blasey Ford; and perhaps most of all, the political style of President Trump, which Democrats view as exceedingly offensive and many Republicans have come to see as acceptable or even admirable.

(Illustrations by Sam Island)

Yet in that map — and in those expanding blue dots — was a clue to another lens, one that often gets short shrift in explaining the fracturing of our country. That lens is economics — specifically, jobs. Red and blue America aren’t separated just by their cultural politics; they are separated by sharp differences in how their economies have developed over the past half-century. And those economic differences can, in turn, explain many of the cultural differences that so bedevil our political system.

There are, of course, a number of different sectors of the American economy, and those sectors can have varying kinds of political influence on the people who work in them. But it’s the changing dynamics of two particular sectors — the older industrial economy and the newer ideas economy — that explain how the current U.S. electoral map came to be. Which is why, here in Washington, if we want to formulate policies that might begin to heal our democracy, we need to pay attention not just to ideology and culture, but also to what those blue dots are telling us about where and whether people go to work each day.

President Trump and former president Barack Obama have both claimed credit for the booming economy. Who's right? (Meg Kelly/The Washington Post)

Over the past 50 years, America’s industrial economy — based in the production of steel, ships, cars, textiles and other goods that were often made by factory workers on assembly lines, plus the service jobs that flourished around them — has declined substantially. Many of the older industrial sectors have become automated; they produce more with fewer workers. Other industries have moved abroad to lower their costs or have closed down in the face of foreign competition, particularly, over the past 15 years, from China. Between 1979 and today, the number of manufacturing jobs has plummeted from 19.4 million to 12.7 million.

The older industrial economy was based in cities and towns — Midwestern locales like Chicago, Gary, Detroit, Muncie, Akron, Allentown and Pittsburgh; and Southern towns like Mobile and Greensboro. The blue-collar workers tended to live in the cities, and the white-collar office workers and managers in the suburbs. As the older industries have fallen into disrepair or moved, some of the towns and cities have fallen on hard economic times. Many residents have moved to nearby suburbs; their children, if they were able to, left as soon as they finished school.

Alongside the decline of this old economy, a new, knowledge-based economy has arisen. This economy specializes in ideas — embodied in such goods as pharmaceuticals, semiconductors, movies and software. MIT economist Peter Temin has dubbed this sector “FTE”: finance, technology and electronics. In recent years, metropolitan areas identified with FTE have prospered and expanded outward. Some of the FTE areas, like Chicago, Los Angeles and Seattle, are former centers of goods production that have managed to reinvent themselves; others, like Austin and Northern Virginia, are places where the economy was long rooted in government and education. In all of these areas, the older distinction between the city, where production takes place, and the suburbs, where the white-collar workers live, has broken down. Microsoft is a Seattle company, but it is located in a suburb. New Jersey’s pharmaceutical industry is suburban, and much of New Jersey itself is a contiguous suburban metro area.

Metropolitan areas that specialize in a new, knowledge-based economy have prospered and expanded outward.

These areas often have one or more major universities. They host a high percentage of college-educated workers (frequently with advanced degrees), some of whom are highly skilled immigrants. They also include a sizable class of service workers, who are often immigrants and who clean the buildings, mow the lawns, make the beds, drive the taxis and take care of the children of two-earner families. Some of these areas, like Chicago and Los Angeles, include older, low-income, mostly African American inner-city neighborhoods; but African Americans have also increasingly moved into middle-class suburbs like those of Prince George’s County outside Washington, D.C. In fact, from 2010 to 2014, the African American population in the suburbs of the 20 largest metro areas grew by 7.1 percent, while the urban population grew by a bare 0.1 percent.

The regions built around FTE are almost always geographically distinct from the old industrial areas and from areas dominated by agriculture or resource extraction. The separation of the regions has proved to be self-reinforcing, as new high-tech firms seek to be near other high-tech firms and in areas where there are major universities and a high percentage of college-educated workers. In “The New Geography of Jobs,” economist Enrico Moretti has described this process as “geographical agglomeration.”

If you want to see geographical agglomeration in action, look no further than the now-concluded battle over where Amazon.com would locate its next headquarters. (Amazon CEO Jeffrey P. Bezos owns The Washington Post.) The finalists included FTE locations like Austin, Chicago, Atlanta, Los Angeles, Philadelphia, Boston and Denver; the winners — New York and the D.C. metro area — are two of the most FTE-friendly places in the country.

These geographically separate economies have produced very different ways of living — and, crucially, very different personal identities. Identity — the result of imagining ourselves as part of a larger group or cause — invariably plays an essential role in all of our lives. It can contribute to a sense of pride and boost self-esteem; it can even — in the case of an extended family, a religion or a nation — ward off the fear of our own death by allowing us to feel connected to a group or a set of principles that will outlive us.

Many Americans (primarily but not all white) who once lived comfortably in older Midwestern and Southern towns have had important parts of their identity stripped away by the transformation of the U.S. economy. Many of them once enjoyed lifetime employment from the same company and could identify with that company — whether it was General Motors or Sears. They also may have enjoyed the protection and solidarity of belonging to a union. They lived in neighborhoods and frequented the same bars, restaurants, churches and bowling alleys. They and their friends had gone to the same high schools and followed the same local teams. They owned their homes and protected them by owning guns. Many of the men had served in the armed forces and belonged to veterans’ groups.

Move ahead to now: The company has left. The union is gone. The neighborhood is gone. Many of the working-class whites, like the Trump supporters in Ohio I interviewed for my last book, have moved to nearby suburbs, where the main public square is the shopping mall. As identities made possible by the old jobs and the old economy have faded, other identities — ones often associated with hard-line conservative politics — have both endured and filled the void: strong identification with the traditional family, with the home (for which these voters see gun ownership as an essential means of protection), with church and religion, with the flag and the nation. Interwoven among these identities are ones that are fundamentally rooted in resentment: toward undocumented immigrants whom they believe their taxes subsidize; toward both legal and undocumented immigrants who they see as upending the mores and language of their hometowns; toward those minorities who, in their minds, benefit unfairly from affirmative action; and toward distant elites in the cities who project disdain for them and their way of life.

People in industrial America have had many of their identities stripped away by the decimation of the old economy.

These Americans formed much of the political base for the religious right of the 1980s and ’90s, the gun rights movement, the anti-immigrant movement and the tea party movement. They now provide the most fervent backing for Trump’s presidency. His electoral college majority in 2016 was based on their support in states like Ohio, Pennsylvania and North Carolina, together with more traditional Republican support from small and big business and from states like North Dakota and Oklahoma, which are dominated by agriculture and resource extraction.

In the FTE areas, the situation could not be more different. Whereas the people who still live in industrial America have had many of their identities stripped away by the decimation of the old economy, the residents of new metropolitan centers suffer if anything from a surfeit of fluid identities. They celebrate Thanksgiving and would defend the United States if it were attacked, but Trump’s slogan, “Make America Great Again,” has little meaning for them. They don’t look back upon a golden age of GM and Sears and the neighborhood pub. They identify as family members or parents, but their conception of family has been significantly broadened by the feminist and sexual revolutions that began in the 1960s.

They may have fond memories of the places where they grew up, but many take more pride in the university they attended. (When I first came to Washington in 1982, I used to amuse myself by privately speculating how long it would take for a downtown hotshot to tell me what university — invariably Ivy League — he had graduated from.) They often belong to professional associations. They derive their identities in part from the products they produce — software, articles, movies — and from the prestigious firms where they work. They are more likely to be part of experimental families, more likely to be gay or have gay friends, more likely to agitate for LGBTQIA rights. (Even in 2018, how many residents of middle America can accurately parse those initials?) They don’t think of themselves as tied to one city. They save their money to travel. They identify as Americans, but also as cosmopolitans. They recoil at Trump calling himself a “nationalist.” They see his supporters as ill-educated bigots, and they see themselves as part of a new global network linked by the Internet.

True, these are sweeping characterizations, and not everyone who lives in FTE areas adheres to them. For one thing, not everyone writes code for a start-up or has graduated from college; invariably, these areas have sizable low- or mid-wage service industries. Yet it is reasonable to assume that those FTE residents who work in service are not immune to the broader values and outlook of the economy that surrounds them. As I told my daughter when she moved to the Bay Area a decade ago, people there won’t want to know what job you have; they’ll want to know what you are “into.” The barista may also be an aspiring actor; the Uber driver (as one in Houston informed me) makes rap videos; the landscaper may have built (as ours did) a political website.

The Democrats’ electoral college majorities in the Barack Obama years and their popular majority in 2016 were powered, in part, by the multiethnic and multiracial members of this urban-suburban FTE economy and culture. Their growing ranks offered a powerful (and overlapping) supplement to the ranks of minority voters who — even when they do not live in FTE areas — have long placed, and continue to place, their faith in the Democrats as the party of civil rights, and of government assistance for those in need.

This electoral coalition is, of course, far from stable — it is riven, for instance, with conflicts over neo-liberalism vs. progressivism and over how much to emphasize racial justice and affirmative action — but it persists and grows because of common opposition to what the Trump coalition stands for. And like the Republican coalition, it is at least partly explained by the kinds of jobs that exist in the places where many of these voters live.

So how did the divide between the different American economies manifest in the 2018 U.S. House races? Let’s start with Virginia, specifically the counties of Northern Virginia and those outside Richmond and Norfolk. These suburbs and exurbs had once been heralded as Republican strongholds, with Democratic support in Richmond or Norfolk strongly linked to African American voters and civil rights; but in 2018, Democrats won almost the entire area stretching from the Northern Virginia suburbs down to Norfolk and Virginia Beach and over to Richmond and its suburbs. Trump was a factor, but so was the spread of the knowledge economy. In Loudoun and Fairfax counties, where Democrat Jennifer Wexton defeated Republican incumbent Barbara Comstock, high-tech firms line the highway to Dulles Airport, and nearly 59 percent of Loudoun residents and 60 percent in Fairfax have at least four-year college degrees.

In Illinois, Democrats extended their reach beyond Chicago and the Cook County suburbs like Evanston to what had been Republican bastions in predominantly white and upscale DuPage and McHenry counties. These counties have become part of the greater Chicago new economy. DuPage County, where Democratic businessman Sean Casten ousted Republican Rep. Peter Roskam, now boasts the Illinois Technology and Research Corridor. Nearly half its residents have four-year college degrees. Very similar results occurred in what had once been thought of as Republican exurbs adjoining metropolitan areas in New Jersey, New York, Pennsylvania, Minnesota, California, New Mexico and Washington state.

Democrats also extended their reach to metropolitan areas in the South. Newt Gingrich’s House Republican majority in 1994 was based in part on places like the Atlanta suburbs of Fulton, Cobb and Gwinnett counties. But in this election, Democrat Lucy McBath defeated incumbent Republican Rep. Karen Handel in Fulton and Cobb, and Democratic challenger Carolyn Bourdeaux managed to force a recount in Gwinnett — in a district that had not previously been competitive — before ultimately losing. These counties are very much part of greater Atlanta’s new economy. In McBath’s district — home to Alpharetta, which brands itself as “the Technology City of the South” — 56 percent of eligible voters have college degrees and 21.6 percent have advanced degrees.

In Georgia’s major statewide race, Stacey Abrams nearly became the nation’s first African American female governor. Yet black turnout — which only went from 29 percent of the electorate in 2014 to 30 percent in 2018 — was not the main factor in her impressive showing. Instead, the statistic that best explains her near-win was the flip in college-educated voters, who went from 55-45 Republican in 2014 to 54-45 Democrat in 2018.

Something very similar happened in Houston and Dallas, where Democrats won in highly educated, wealthy suburban districts that Republicans had long controlled. (Democrats even picked up a seat in upscale Charleston, S.C., and the coastal resort areas.) Democrats also scored in other metropolitan areas that Republicans had previously dominated. In Kansas City, Kan. — the home of Sprint — Sharice Davids, a Native American lesbian, ousted Republican Rep. Kevin Yoder. If you take the 19 American cities that Amazon listed as finalists for its new headquarters, all of them now have Democratic House members.

By contrast, Republicans remained strong in places like the newly created congressional district in southwestern Pennsylvania — made up of small towns that had been manufacturing centers but had lost jobs during the Great Recession. Indeed, according to a post-election analysis by Priscilla Alvarez, Frankie Dintino and Caitlyn Hampton in the Atlantic, Republicans won 68 percent of the vote in manufacturing towns, which are primarily in the Midwest and South.

In southern Minnesota, meanwhile, Republicans flipped a seat that is a microcosm of the electoral divide. The district is split between Rochester — a midsize city of 115,000 that contains the Mayo Clinic and votes Democratic — and former manufacturing and farm towns to the west that have attracted migrant farmworkers, have very few college graduates and have become dependably Republican. In the 2018 election, the Republican candidate, relying on his margin outside Rochester, narrowly upset the Democrat.

To be sure, not all of this year’s results can be explained by the clash between economies. In the House races, Democrats were able to win over some Trump voters by warning of Republican efforts to allow insurance companies to deny coverage to people with existing conditions. Democratic Senate candidates in Texas and Arizona benefited from a boost in Hispanic support. And there is also little doubt that under a less incendiary president, Democrats might not have done as well in places like suburban Atlanta or Houston. But the trend toward political polarization between the two economies did not begin with Trump and won’t end after he leaves office. He merely accentuated it.

As the metropolitan areas grow and expand at the expense of older industrial towns and rural areas, they will — barring gerrymandering — make it easier for Democrats to maintain the House and also to win popular majorities in presidential elections. At the same time, Republicans may be able to maintain control of the Senate, where a relatively unpopulated state with no large new-economy metropolitan area can send the same number of representatives to Capitol Hill as California or Virginia. In this election, Democrats easily carried the House but lost Senate seats in Missouri, North Dakota and Indiana, three states that have few, or any, FTE metro areas. In other words, a split Congress — with all the gridlock that suggests — may become the norm in American politics.

The divisions between the two economies also make more likely the prospect of the electoral college — which tilts in favor of less populated states that are not dominated by metropolitan areas — failing to reflect the will of a majority of voters. That, in turn, may raise questions about the legitimacy of our presidential elections. Results like 2000 and 2016, when Republicans lost the popular vote but won the presidency, could become increasingly common.

Perhaps the most troubling — and thorny — upshot of these changes is that they have given rise to the latest culture wars, which in turn serve to distract us from addressing the economic issues that have caused so many of our divisions in the first place. Trump, to his credit, seems to have geared his trade policy toward reviving manufacturing in the forgotten regions of middle America. But whatever benefit Americans may get from Trump’s trade policies — and it’s still not clear there will be any — is certain to be outweighed by his never-ending attempts to inflame cultural divisions by inciting nativist fears and racial hatred.

It’s hard to imagine America finally confronting the differences in prosperity and prospects between red and blue areas as long as Trump and his tweets occupy center stage, transfixing Democrats and Republicans alike. Yet for the sake of America’s future, we are going to have to find a way to talk honestly about the massive divide caused by the two economies — and somehow, start working to bridge it.

John B. Judis is the author of “The Nationalist Revival: Trade, Immigration, and the Revolt Against Globalization.”