In Sunday’s NYT, Greg Mankiw relies on a pair of studies by Ed Manfeild and Diana Mutz to suggest that blue collar workers support Trump’s anti-free trade economics because they are psychologically prone to isolationism, nationalism, and ethnocentricity, and further, that more education seems to soften people’s views on these issues. I remain skeptical.
The studies show that a person’s position on free trade is largely driven by their opinion about whether they believe free trade is good for the country and, to a lesser extent whether they believe it is best for themselves. While a person’s views on isolationism and ethnocentrism are one of the few statistically significant predicators of their position on trade, those indicators scarcely improve one’s ability to predict a person’s position on trade beyond knowing whether they believe trade is good for the country and/or themselves. The inability of these additional variable to add substantial predictive power despite their statistical significance suggests that a person’s positions on these issues may be correlated with one another rather than symptoms of deeper psychological drivers of anti-trade—intolerance or ignorance, for example.
Why might these positions be correlated with one another rather than causal? It would hardly be surprising if higher-skilled/higher-income workers were more open-minded about using tax revenues to intervene internationally or aid newly arriving immigrants, rather than feeling strongly about using them for the benefit of one narrow objective over another. On the other hand, those competing for the benefits of government spending—lesser-skilled workers and retirees, for example—may feel more strongly about the validity off their self interest and be more prone to hostility toward interests competing against them for a limited amount of government spending (or government restrictions that slow growth for the benefit of one special interest group at the expense of others). One need only look to sports to see similar psychological effects.
That’s not to say political beliefs are solely motivated by self interest. But is it any surprise that that white college grads skew Republican or that Democrats are more likely than Republicans to support an increased minimum wage and that both are more prone to believing their position is better for America too?