A continuing refrain of Occupy Wall Street protesters has been “student debt is too damn high,” as James Surowiecki wrote in The New Yorker. In some cases — like for the college graduate profiled in a recent article in the Chronicle of Higher Education who has $100,000 in debt and uncertain job prospects — this is unarguably true. But such cases make for dramatic reading precisely because they are so rare. The first thing to note is that most of those with that much debt have graduate degrees; it is difficult to accumulate that much debt in an undergraduate program....