As I recall, "trades" meant working with the hands while "vocations" were more varied. Trade schools were targeted toward males while vocational training could attract both genders. I'm thinking that vocational training gave way to or overlapped such as were offered in junior colleges and technical schools. For instance, doctors and nurses were required to have college degrees. Assistants to doctors and nurses didn't need the same level of academic training and vocational and junior colleges could fulfill requirements for their employment. I don't know where things have gone since then as government regulation and licensing practices have turned everything upside down for many career choices. But you're right that the trades were a different animal. People who entered those generally were introduced by a friend or family member. There wasn't an application process or tuition to be paid either. Eventually, the complexity of some did require greater knowledge. HVAC is one example of simple morphing to high-tech needs.
How do I know that? Because guess who's on his bus as he travels around Ohio today? Mitt Romney. Why would you want a 2 time loser endorsing you?! Traveling with you? Standing on the stage with you? Oh Kasich, you just blew it big time.

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