Democrats and Rising Income Inequality

Mark Thoma finds that income inequality has little to do with political parties:

"If we turn to data that include the top 1%, we find only a weak association between president’s party and changes in inequality since the 1970s. Republican and Democratic presidents have pursued contrasting tax policies, and those policies appear to have made a difference for inequality. But their impact has been swamped by trends in pretax income. At the moment we know relatively little about the factors driving the dramatic increase in the share of economic growth going to those at the top of the distribution, and even less about what role presidents have played."

Me: Looking for reasons? Try technology and globalization, though I doubt whether inequality has expanded anywhere near when Thoma thinks