Up until then, "high school" or its equivalent was something privileged kids got to attend. Or perhaps one gifted child in your family would stay in education, while the other children went to work. With the uniform enrollment of compulsory education, however, privilege became democratized, in a sense. We learned to look down on working folk in favor of educated folk. Staying in school became the aspiration and the ideal. This isn't wrong-headed per se, but it is a bit... remiss in its remembrance of why we "stayed in school". We didn't stay in school to become better people, or to enhance critical thinking, or to have a "vibrant democracy" (indeed, a "vibrant democracy" needs education at the baccaleureate level like a dogs needs to learn trigonometry to be a good dog.) We stayed in school because people were using child labor against adults and destroying society in the process. Child labor destroyed the family unit, undermined parental authority, and blurred the distinction between "fathers" and "bosses".
Education is important to a democracy, but we shouldn't then just automatically accept the idea that college education is important to a democracy. Remember, when everyone made those glittery quotes about democracy and education, they were making it from a standpoint of an 8th grade (or its equivalent) minimum. That is, people need to be literate, they didn't need to be college grads. We take literacy for granted, but literacy is 90 percent of what is meant by sustaining a democracy.
Whereas child labor did terrible things to people, and to families, institutionalized schooling has its own side effects. Rather than return children to their families, we handed them over to teachers and administrators, which has its own disagreeable bourgeois side-effects; namely the idea that working in an office is the penultimate end of every man, woman and child, and anything less means you're a lesser breed. (I speak of the bourgeois in cultural terms, not economic.)
So now it is the case that we find ourselves ridden with student debt and calls for government subsidy and support to help more people go to college. But going to college isn't a productive thing. We're essentially paying people not to work, or rather borrowing against the future so we don't have to work now. In any case, you're taking on more debt to reduce the productive output/capacity of a population. When you do that, you're not making up ground, you're just losing it.
We must not be deceived by the patronizing "respect" shown to the working class by bourgeois liberals and their ilk, either. Working for a living, rather laboring for a living is "respectable" in the sense that "other people do it and god bless them." Much like welfare, elements of the bourgeois "support" welfare if only because "Oh we'll never need it ourselves." It's something "other people" have to worry about, but you'll never take it, because, well, because you're better than that.
In much the same way, people "support" trades the way they support inter-racial marriage. It's fine, in theory, as long as their kids don't get involved with it. Oh we all respect a carpenter sure, but it's not like we want our kids to be carpenters. We spent all that time and money saving up for college! The only solution to this is once again forced enrollment. High school should end at the age of 16, and we should all be forced into a trade for two-years training time. If you want to go to college fine, but we ain't paying for it. This isn't tyrannical, or at least it isn't any more tyrannical than what we already have: forcing every child into 4 years of college prep for no particular reason other than it sounds good. In reality, we're prepping every child for a lifetime of mortgaged education expenses. Indeed, education debt cannot be bankrupted away. The mortgage is not on a piece of property, it is on your life, your soul, your person.
How will this help the economy? Well, for once it will boost wage receipts and reduce debt load. This helps us spend more money rather than take on more debt. It helps remain freer from the clutches of banks, and maintain some semblance of autonomy from the financial elite (however fleeting). Education is the next bubble, people have already said. Financing college is the new real estate, and we know how that works out.