In our discussion of the "great risk shift," we haven't yet mentioned one increasingly risky area of middle-class life: college tuition.

A generation ago, we understood that we all have a stake in college affordability. More college graduates strengthen our economy and our democracy.

In recent decades, however, college leaders, politicians, and the media have focused on higher earnings as the primary benefit of college. The logical conclusion: if college is for the students, students should pay for it.

The philosophical shift has lead to a "privatization" of higher education. In the last 30 years, tuition has nearly tripled at both public and private four-year colleges (after adjusting for inflation). State universities increasingly rely on tuition revenue as public support wanes. Student debt has skyrocketed, and the median at public colleges is nearly $20,000.

We have lost sight of the complete picture. While students clearly do benefit from college, there are are also important economic, social, and democratic benefits for the rest of us.

And while college is a very good investment on average, it is not a sure bet. Income inequality is rising among college graduates. Particularly troubling are students who gamble on college and lose, dropping out with large amounts of student debt.

College students and their families are hearing the same message as millions of other families in the middle class or trying to join it: you're on your own.