To steal and expand upon a point Betsey Stevenson made on Twitter earlier, it's striking the extent to which employment growth over the past month and the past year was concentrated among college graduates. In part that's just what you expect from a weak labor market. When workers arescarce, you hire underqualified people and try to train them. When workers are plentiful, you hire the most qualified people around and count yourself lucky. But polarization in the American job market is nothing new and we see a continuation of a trend that was visible across the growth of the aughts.