I have another article at MoneyWatch:
Sagging job growth: It's not a skills gap, by Mark Thoma: Many economists believe the rise in inequality can be explained by factors that have increasingly rewarded college-educated workers over those without a college degree. This "skills premium" has caused the middle class to shrink and polarized the labor market. The solution to these problems is the often-heard call for improved education and retraining programs that will give workers the skills they need to thrive in modern economies.
Employment in manufacturing industries has been hit particularly hard over the last few decades, and economists have pointed to work by David Autor, an economics professor at MIT, and others suggesting that this has resulted more from technological change than from globalization and declining bargaining power of workers (e.g. due to the power of unions).
According to this view, outsourcing is not the main problem. ... However, new work by Autor and several prominent co-authors calls this into question...