LIKE ANY MAJOR METROPOLIS, Los Angeles has its normal sea of troubles, but there are two fundamental problems that really define the city and the challenges it confronts. The first, with which the Weekly has dealt extensively of late, is the quality of its air. The second, which may be even harder to fix, is the quality of its economy. Over the past quarter century, Los Angeles has been downwardly mobile, with its middle class shrinking to a fraction of its former size. Both these problems — air quality and, even more, the vanishing middle — afflict the nation generally. But Los Angeles has opened such a wide lead on every other city that we’re not just quantitatively different; we’re qualitatively in a class by ourselves.

Two surveys that have come out in recent months spell out the economic problem in the starkest of terms. In June, the Brookings Institution released a study titled “Where Did They Go? The Decline of Middle-Income Neighborhoods in Metropolitan America,” a survey of the nation’s 100 largest metropolitan areas in which Los Angeles has the starring role as the city that’s fallen the furthest. Looking at census-tract data from the 1970 and 2000 census reports, the study notes that whereas 58 percent of neighborhoods in those metropolitan areas were middle income in 1970, just 41 percent were in 2000. It’s in L.A., though, that the middle has truly vanished. Just 28 percent of Los Angeles neighborhoods are middle income. That ranks a cool 100 out of the 100 largest metro areas.

As with neighborhoods, so with families. A scant 17.4 percent of L.A. families were middle income in the 2000 census, which ranked us next to last. (New York brought up the rear at 16.2 percent.) Angelenos were both richer and poorer: 40.4 percent of local families had low incomes; 42.2 percent had high incomes. The problem is that the poverty of the poor exceeded the wealth of the rich. Between 1970 and 2000, real median family income in L.A. declined — that’s declined — by 5.7 percent.

This didn’t happen in other cities. Brookings looked most intently at 12 metropolitan areas, including L.A., Chicago, Philadelphia, Oakland and Baltimore — hardly a list composed exclusively of boomtowns. Los Angeles was the only one in which median income went down.

The Los Angeles of 1970 was another country, a different world, from what it is today. It was home to a giant aerospace industry and the second-largest auto-manufacturing center in the nation — both industries unionized, both helping give the region a vast and vibrant middle class. Construction and trucking were largely unionized then too. Today, those jobs and the people who once held them are long gone — many hightailing it to other states in the early and mid-’90s, when aerospace collapsed, in search of the middle-income jobs no longer found in L.A.

Los Angeles rebounded from the recession of the early and mid-’90s, of course, but its middle class did nothing of the kind. Adapting brilliantly to the flood of low-skilled and poorly educated immigrants, the local economy created thousands upon thousands of new shit jobs in fast-food joints and off-the-books factories, in driving trucks and building homes for nonunion employers, in mowing lawns and taking care of the kids. A recent survey, “L.A. Labor Market Strengths and Weaknesses,” from the Los Angeles Economic Roundtable, shows, for instance, that the industry that created the most private-employer jobs between 1996 and 2002 was “limited-service eating places.” Again, we’re creating high-end jobs as well, many in entertainment. But 24 percent of employed L.A. city residents, the Roundtable concludes, are poor.

The absence of jobs in the middle means that traditional ladders of social mobility that were there for generations of immigrants (from either foreign countries or domestic rural areas) throughout American history aren’t there now. And as the poor are cut off from the prospect of middle-income employment, they’re cut off from the prospect of living in middle-income neighborhoods too. Nationally, according to Brookings, 55 percent of low-income families lived in middle-income neighborhoods in 1970. By 2000, just 37 percent did. Brookings didn’t publish the figures for L.A., but they have to be a lot worse.

IN A SENSE, BROOKINGS HAS PROVIDED the statistical verification, if one were needed, for the premises, if not the ensuing action, of Crash. The L.A. that emerges from its study, and the Roundtable’s, is all gap and no bridge.

There are, of course, some notable attempts at bridge building. The victories of the labor movement and living-wage activists to win higher wages for public-contract workers or employees at projects built with governmental assistance or tax breaks have moved a number of workers (not nearly enough) out of poverty. So has the growth of unionization among such low-wage workers as janitors and (happening just now) security guards. But the inability of supermarket workers a few years back to block the imposition of wage and benefits cuts for new hires reduced the number of local middle-income jobs.

The challenge for the city is how to fight these battles on the much larger scale required to rebuild a middle class — and that’s certainly how the mayor sees it. Antonio Villaraigosa’s war over the schools is about all manner of things large and small, but at its largest, it stems from a belief — at minimum, a hope — that an educated work force will rebuild the middle class here.

If you look at the incomes of individual workers, that seems a logical inference. Among employed L.A. city residents, those with college degrees have median annual incomes of $57,000, the Roundtable study says, while those who haven’t finished high school have yearly incomes of $19,000. On an individual level, and in aggregate as well, education can only help.

But how much? Is it still true, as Bill Clinton argued during his 1992 campaign for president, that what you earn depends on what you learn? Or has the brave-new-world economy decoupled even learning and earning? According to an article this spring in Foreign Affairs by Alan Blinder, the Princeton economist whom Clinton appointed to the Federal Reserve’s Board of Governors, the number of American jobs that can be performed abroad far more cheaply will in several years total somewhere between 42 million and 56 million. That includes virtually all manufacturing jobs, but it also includes the jobs of many highly educated professionals that, through the miracle of electronic communications, can be performed by Chinese and Indian professionals who work a lot cheaper. (Routine legal contracts, Blinder writes, can be drafted in Delhi, though legal jobs requiring personal contact — divorce lawyers, for instance — will stay here. Now, there’s a vision for our economic future.)

With the coming of a global white-collar labor market to rival the blue-collar wave that hit auto assembly, to what degree will education really be the magic bullet? In 2002, according to the Bureau of Labor Statistics, 26.9 percent of all jobs in the U.S. required a college degree. In 2012, the bureau estimates, that figure will rise to 27.9 percent — a whopping 1 percent increase.

In truth, there’s not a political tendency anywhere on the planet that knows how to preserve the middle-class character of advanced economies in the face of globalization — and certainly not in the U.S., where companies, more than in any other nation, reflexively seek to boost profits by doing anything they can to reduce labor costs. None of this exactly negates the idea that education is a prerequisite for upward mobility; it just limits the degree of broad upward mobility that’s possible. It certainly doesn’t diminish the imperative for better schools. L.A. clearly needs them. It just needs a whole lot — and it’s hard to say what, exactly — else.

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