Back in 1987 my Princeton colleague Alan Blinder published a very good book titled “Hard Heads, Soft Hearts.” It was, as you might guess, a call for tough-minded but compassionate economic policy. Unfortunately, what we actually got — especially, although not only, from Republicans — was the opposite. And it’s difficult to find a better example of the hardhearted, softheaded nature of today’s G.O.P. than what happened last week, as Senate Republicans once again used the filibuster to block aid to the long-term unemployed.

What do we know about long-term unemployment in America?

First, it’s still at near-record levels. Historically, the long-term unemployed — those out of work for 27 weeks or more — have usually been between 10 and 20 percent of total unemployment. Today the number is 35.8 percent. Yet extended unemployment benefits, which went into effect in 2008, have now been allowed to lapse. As a result, few of the long-term unemployed are receiving any kind of support.

Second, if you think the typical long-term unemployed American is one of Those People — nonwhite, poorly educated, etc. — you’re wrong, according to research by the Urban Institute’s Josh Mitchell. Half of the long-term unemployed are non-Hispanic whites. College graduates are less likely to lose their jobs than workers with less education, but once they do they are actually a bit more likely than others to join the ranks of the long-term unemployed. And workers over 45 are especially likely to spend a long time unemployed.

Third, in a weak job market long-term unemployment tends to be self-perpetuating, because employers in effect discriminate against the jobless. Many people have suspected that this was the case, and last year Rand Ghayad of Northeastern University provided a dramatic confirmation. He sent out thousands of fictitious résumés in response to job ads, and found that potential employers were drastically less likely to respond if the fictitious applicant had been out of work more than six months, even if he or she was better qualified than other applicants.