According to Ben Bernanke, former head of the Fed, student loans are mostly backed by the government while mortgages, which sparked the 2008 financial crisis, were held by publicly traded financial institutions susceptible to panic.
This article by Reuters highlights the skyhigh levels of student debt in the US, set against a poor outlook for jobs. Without wealthy parents, ambitious young people are forced to taken on student debt. This situation will no doubt color the views of many young Americans ahead of the US presidential election.
This article highlights the risks for young people in other countries, with high levels of student debt. In Europe for example, it is hard for young people to find proper jobs to utilize effectively their education. Typically, student debt levels in Europe do not yet reach American levels.
Part of the problem is to do with technology changing the outlook for jobs and educational establishments not matching educational services with demand for jobs.