In fact, the income differentials understate the chasm between college and high school grads. In the 1970s, high school and college grads had very similar family structures. Today, college grads are much more likely to get married, they are much less likely to get divorced and they are much, much less likely to have a child out of wedlock.

Today, college grads are much less likely to smoke than high school grads, they are less likely to be obese, they are more likely to be active in their communities, they have much more social trust, they speak many more words to their children at home.

Some research suggests that college grads have much bigger friendship networks than high school grads. The social divide is even starker than the income divide.

These two forms of inequality exist in modern America. They are related but different. Over the past few months, attention has shifted almost exclusively to Blue Inequality.

That’s because the protesters and media people who cover them tend to live in or near the big cities, where the top 1 percent is so evident. That’s because the liberal arts majors like to express their disdain for the shallow business and finance majors who make all the money. That’s because it is easier to talk about the inequality of stock options than it is to talk about inequalities of family structure, child rearing patterns and educational attainment. That’s because many people are wedded to the notion that our problems are caused by an oppressive privileged class that perpetually keeps its boot stomped on the neck of the common man.

But the fact is that Red Inequality is much more important. The zooming wealth of the top 1 percent is a problem, but it’s not nearly as big a problem as the tens of millions of Americans who have dropped out of high school or college. It’s not nearly as big a problem as the 40 percent of children who are born out of wedlock. It’s not nearly as big a problem as the nation’s stagnant human capital, its stagnant social mobility and the disorganized social fabric for the bottom 50 percent.

If your ultimate goal is to reduce inequality, then you should be furious at the doctors, bankers and C.E.O.’s. If your goal is to expand opportunity, then you have a much bigger and different agenda.