One has to think that this is also one of the factors driving our cultural divide.

The national media really does work in a bubble, something that wasn’t true as recently as 2008. And the bubble is growing more extreme. Concentrated heavily along the coasts, the bubble is both geographic and political. If you’re a working journalist, odds aren’t just that you work in a pro-Clinton county—odds are that you reside in one of the nation’s most pro-Clinton counties. And you’ve got company: If you’re a typical reader of Politico, chances are you’re a citizen of bubbleville, too.

[…]

Where newspaper jobs are spread nationwide, internet jobs are not: Today, 73 percent of all internet publishing jobs are concentrated in either the Boston-New York-Washington-Richmond corridor or the West Coast crescent that runs from Seattle to San Diego and on to Phoenix. The Chicagoland area, a traditional media center, captures 5 percent of the jobs, with a paltry 22 percent going to the rest of the country. And almost all the real growth of internet publishing is happening outside the heartland, in just a few urban counties, all places that voted for Clinton. So when your conservative friends use “media” as a synonym for “coastal” and “liberal,” they’re not far off the mark.

The theoretical cause is fascinating.

But economists know something the internet evangelists have ignored: All else being equal, specialized industries like to cluster. Car companies didn’t arise in remote regions that needed cars—they arose in Detroit, which already had heavy industry, was near natural resources, boasted a skilled workforce and was home to a network of suppliers that could help car companies thrive. As industries grow, they bud and create spinoffs, the best example being the way Silicon Valley blossomed from just a handful of pioneering electronics firms in the 1960s. Seattle’s rise as a tech powerhouse was seeded by Microsoft, which moved to the area in 1979 and helped create the ecosystem that gave rise to companies like Amazon.

As Enrico Moretti, a University of California, Berkeley, economist who has studied the geography of job creation, points out, the tech entrepreneurs who drive internet publishing could locate their companies in low-rent, low-cost-of-living places like Cleveland, but they don’t. They need the most talented workers, who tend to move to the clusters, where demand drives wages higher. And it’s the clusters that host all the subsidiary industries a tech start-up craves—lawyers specializing in intellectual property and incorporation; hardware and software vendors; angel investors; and so on.