On Saturday, Salon ran a terrific article by Suzanne Mettler with this headline: “More Bad News for Millennials: College Is Actually Making Inequality Worse” [http://www.salon.com/2014/03/15/more_bad_news_for_millennials_college_is_actually_making_inequality_worse/].

Given the current attention to the issue of income inequality, the headline does a disservice to what is actually a very complex analysis of the economic impact of enrollment and degree-completion rates.

More specifically, the headline seems to locate this article in the middle of the growing debate on the value of a college degree. On the one hand, there has been a chorus of voices pointing to the employment and income advantages of those holding college degrees at every level, from associates to professional degrees and, therefore, calling for dramatic increases in enrollment as an economic necessity. On the other hand, there has been a competing chorus of voices pointing to the increasingly high debt accrued by college graduates and the under-employment of many of those graduates during and immediately after the Great Recession and, therefore, calling for a reappraisal of which college degrees offer economic advantages and for what percentage of students the cost is economically justifiable.

For Mettler—and this is very much to her credit—this debate over the value of a college degree is a non-issue. In countering the arguments of Right-Wing ideologues who have continued to frame discussions of higher-education issues in the rhetoric of privilege, Mettler tracks degree-completion rates since World War II and demonstrates that when those rates rose dramatically, as they did in the 1950s and 1960s, the income and standard of living of the average American worker increased proportionately. But when college-completion rates flattened out as they did in the 1970s and 1980s, or increased much more slightly, as they did in the 1990s, and 2000s, the income and standard of living of the average American worker stagnated and even declined.

Very insightfully, Mettler also emphasizes that looking at broad averages can be misleading: that is, although the percentages of working Americans holding degrees and of “college-age” individuals enrolled in college are broadly comparable to rates in other economically developed nations, the degree-completion rate among “college-age” Americans has been steadily declining in comparison to that rate in other developed nations.

So, what Mettler is actually focusing on is the widening gap in degree-completion rates by family income. Students with family incomes in the top ten percent both enroll in college and complete degrees at a very high rate. But the enrollment and degree-completion rates decline significantly even when one surveys students with family incomes in the top 25%. And the rates decline precipitously for students in each income bracket below that.

Higher percentages of students from poorer backgrounds have been enrolling in college, but those increases have not kept pace with the increases in the higher-income brackets, and the enrollment increases have not produced comparable increases in degree-completion rates.

And the major reasons for the low degree-completion rates among lower-income groups are economic. Students from poorer K-12 school districts take longer to complete degrees and the much higher cost of completing degrees often means that they need to work while enrolled, which further slows their progress toward a degree, or that they may simply run out of financial resources—become ineligible for further grants or loans—before finishing.

In short, what Mettler is arguing is that anyone who is serious about addressing income inequality needs to advocating a much larger public investment in higher education. Without such a commitment, the current trends will become only more pronounced.

Moreover, Mettler’s article is an excerpt from her recently published book Degrees of Inequality: How the Politics of Higher Education Sabotaged the American Dream (Basic Books), and in the book, she makes the case that improving access and affordability is not only a matter of social justice, but also an economic necessity. Seventy percent of the U.S. GDP is still produced by consumer spending, and, in shrinking the middle-class that has been the driver of that spending, income inequality threatens the economic prosperity not just of certain classes of people within the nation but of the nation as a whole.

When Mettler’s study is taken together with similar historical treatments of the links between middle-class prosperity and rates of unionization, the case that Far-Right ideology has been serving the interests of the very wealthy at the expense of everyone else becomes very compelling. For that ideology has not just coincidentally undermined collective bargaining and public higher education; it has, instead, very deliberately made those two drivers of upward mobility and middle-class prosperity its primary targets.