Some colleges and some degrees are worth the cost, but as a few other commenters have noted, just having "the piece of paper" is no longer a guarantee of anything (except perhaps of owing student loans that must be repaid!!)
Americans still have the factory-mindset, where Pap went to work in the mill/factory as did all our uncles, neighbors, cousins, etc and the "rich kids" from across town, whose parents went to college, and grandparents went to college, came home with his degree (in anything - didn't matter) and was made assistant manager.
This model long ago became irrelevant, and for multiple reasons.
#1: the manufacturing base is gone and the service industry has replaced manufacturing in many towns, which leads to #2
#2: we live in a predominantly service-oriented world now ("would you like fries with that, sir?") and these jobs don't pay near what the manufacturing jobs paid. In the post-war years, an uneducated high school drop out could work hard in the factory/mill and eventually earn enough to buy a house, and a couple cars, and take his family on vacation every year. Try doing that on your Starbucks or McDonald's or Gap salary!!
#3: The student loan industry has made it possible for anyone with a PULSE to borrow an unlimited amount of money to go to college, and colleges have run the numbers and proclaimed Eureka! While there are still admissions standards at many of your larger more established universities, too many state institutions and most of your for-profits institutions have done the math and realized that Americans still think that ANY cost for that degree is worth it and will borrow to get it.