Basically is the complete absence of an education program like the dual system used in Germany. In the US, if you drop out or even do not attempt advanced education, you can do whatever you want. In Germany you are required to become a apprentice for the job you eventually want to do. Education and qualification is done by your employer then (with final exam by the state).

Apprenticeship is a very old European tradition, and still guaranteeing today that an electrician knows the color of the cables (and a lot of more important things). Too bad the US dropped it.