It’s cold comfort, but the loans put him in good company: Hundreds of billions of dollars of national student-loan debt has now overtaken American credit-card debt, the Wall Street Journal recently reported, using numbers compiled by FinAid.org, a Web site for college financial aid information…

According to a report in the Chronicle of Higher Education, 31 percent of loans made to community college students are in default. (The same report found that 25 percent of all government student loans default.) Default on a student loan and face dire consequences, beyond a bad credit record — which can tarnish hopes of getting a car, an apartment or even a job: Uncle Sam can claim your tax refunds and wages.

Now, take a key argument in favor of getting a four-year degree, the one that says on average, those with one earn more than those without it. Education Department numbers support this: In 2008, the median annual earnings of young adults with bachelor’s degrees was $46,000; it was $30,000 for those with high school diplomas or equivalencies. This means that, for those with a bachelor’s degree, the middle range of earnings was about 53 percent more than for those holding only a high school diploma.

But a lot of college graduates fall outside the middle range — and many stand to make considerably less.