At opposite ends of the pay scale, there are jobs that seem safe from the robot menace, Brynjolfsson said—high-paying creative and managerial work, and non-routine physical work, like gardening. (The smartest machines still struggle to recognize an ordinary kitchen fork if it is rotated by 30 degrees.) As for the 65 percent of us who are employed in “information processing” jobs, Brynjolfsson said, the challenge is to integrate human skills with machine capacities—his phrase is “racing with machines.” He mentioned a biotech company that relied on human workers to refine the physical shapes of synthetic proteins, jobs at which the most sophisticated algorithms remain hopeless. I expressed some doubts about how many jobs there might be in endeavors like this. “The grand challenge is: Can we scale them up?” Brynjolfsson said. “We haven’t seen that yet. Otherwise, employment would be going up rather than down.”
Even among the most committed stagnation theorists, there is little doubt that innovation will continue—that our economy will continue to be buttressed by new ideas and products. But the great question at the center of the growth argument is how transformative those breakthroughs will be, and whether they will have the might to improve human experience as profoundly as the innovations of a century ago. One way to think about economic growth is as a product of human capital and technology: At moments like this, when human capital is not growing much (when the labor force is unlikely to grow, when it is not becoming more educated), all of the pressure rests on technology. For this reason, some economists who think Gordon greatly understates the potential of computers still agree that it will be hard for technology to sustain the growth rates we’ve become accustomed to. “We’re not going to get to 2.25 percent GDP growth—that’s way out on the tail,” Dale Jorgenson of Harvard told me. “There’s going to be a slowdown. It’s not a secular stagnation. It’s a change in demography. And this is a watershed event.”
Provoked by Gordon’s paper, Daniel Sichel of Wellesley and a team of collaborators have worked out a model by which future U.S. growth might match the rates it has historically achieved. It was not a science-fiction scenario, Sichel explained to me; it required a faster rate of improvements in microprocessor technology, and new computer technologies to be adopted quickly by sectors (education, health care) that have tended to move more slowly. But this is Sichel’s optimistic model; his median projection—his sense of what is most likely to happen—isn’t much more hopeful than Gordon’s. That we might continue to experience the kind of growth we’ve enjoyed for the past several decades remains a defensible possibility. But so does Gordon’s idea, that something great is gone.
In 2007, Mexicans stopped emigrating to the United States. The change was not very big at first, and so for a few years it seemed like it might be a blip. But it wasn’t. In 2000, 770,000 Mexicans had come across the Rio Grande, but by 2007 less than 300,000 did, and by 2010, even though violence in Mexico seemed ceaseless, there were fewer than 150,000 migrants. Some think that more Mexicans are now leaving the United States than are coming to it. “We’re never going to get back to the numbers we had in the late nineties,” says Wayne Cornelius, a political scientist at UC–San Diego who has spent the past 40 years studying this cross-border movement. A small part of this story is the increase in border protection, but the dominant engine has been the economic shifts on both sides of the border—it has become easier for poor Mexicans to improve their quality of life in Mexico and harder to do so in the United States. Because migrants from a particular Mexican village often settle in the same American place, they provide a fast conduit of economic information back home: There are no jobs in construction or housing. Don’t come. The Pew Hispanic Center has traced the migration patterns to economic performance in real time: a spike of migration during 1999 and 2000, at the height of the boom; a brief downturn in border crossing after the 2001 stock-market crash followed by a plateau; then the dramatic emptying out after the housing industry gave way in 2006. We think of the desire to be American as a form of idealism, and sometimes it is. But it also has something to do with economic growth. We are a nation of immigrants to the extent that we can make immigrants rich.
These hingelike mechanisms, in which social changes depend upon the promise of rapidly escalating well-being, are studded throughout the aftermath of the second industrial revolution. The United States did not really become a melting pot until the 1880s, when the economy was beginning to draw on the breakthroughs of electricity and the engine and attract migrants from Southern and Eastern Europe. The labors that housework required in the nineteenth century were so consuming that housewives in North Carolina walked 148 miles a year carrying 35 tons of water for nonautomated chores. It took until the fifties for household appliances to decline so much in price that they were ubiquitous; the next decade was the one of women’s liberation. The prospects for African-American employment increased most dramatically during World War II and in the period just after: 16.4 percent of black men held middle-class jobs in 1950; by 1960 it was 24 percent; by 1970, 35 percent. Progressives will often describe the history of social liberation by quoting Martin Luther King Jr.’s line that the arc of the moral universe bends toward justice; the implication is that metaphysics are somehow involved. But this history has also taken place during unique economic times, and perhaps that is not coincidence.