And if it's the latter, then again, why should student loans be special?
If you build a man a fire, he'll be warm for a day.
If you set a man on fire, he'll be warm for the rest of his life.
There is definitely a benefit to society in having an educated populace. An employer will have an easier time hiring educated people for jobs that require it like engineers, doctors, and so forth. While an employer could hire someone without the education and train them, there's a risk you put all this money and time into someone and that someone then quits and gets a job somewhere else that pays him more (likely because they didn't have to pay for his training). Students don't usually have the money to pay for their education (they want the education so they can get the money after all). Companies won't provide that level of training to employees (as the employee can easily quit once they're trained.) So in the free market system education is underutilized and we're less efficient.
So it does make sense for the government to help with that. Student loans, grants, and so forth are forms of that help.
That said, the system is currently broken in that it pushes far too many people through degree programs and the jobs don't exist. Even if the economy was perfect, we're educating too many people, the jobs still wouldn't be there. Most students have a belief that they will all end up doing nice high paid jobs after graduating so they take on the debt. They then graduate and get a real education by not having tons of offers for six figure jobs showering them. And then they complain about their loans. The system is as guilty as anything in encouraging everyone to attend college. When I was in highschool if you weren't planning to go to college after you were stupid. And yet, a figure far short of 100% of jobs require college degrees, and they're not all bad jobs either (though we do need people to do the ones that are perceived as bad jobs all the same.) The system has lots of room for improvement. Make it harder to get the college education and try to encourage degree choices such fill needed vacancies.
As far as the students going bankrupt for existing debt, the interesting thing on all the proposals I've seen from politicians is none of them would help this kid. Lots of proposals to pay more of the schooling, to reduce interest rates on new debt, and so on. Nothing I've seen that covers existing debt. If they passed a law making college free tomorrow I don't see them forgiving existing student loan debt.
While I agree with the OP comment that if you accept the loan you should do everything you can to pay it back, it is disturbing that so many people w/college degrees still carry so much student loan debt years after obtaining their degree.
"A fair exchange ain't no robbery." Tupac Shakur w/Digital Underground