Prior to 2003 and the beginning of the unconventional shale gas gig, the US oil and natural gas industry was profitable, even with prices below $20 WTI; jobs were plentiful and people could make a career for themselves in the oilfield.

In 2003-2004 prices started to rise, and fall, mostly because of leveraged over-supply of unconventional resources. Along with price instability came job instability and upstream employment began dropping. Mass manufacturing of shale wells created more automation; jobs fell more. Debt had a lot to do with this.

Mighty Exxon operated for over 100 years, under different names, with NO debt whatsoever. Then shale came along and it bought XTO. It went downhill from there. Now its $40 B in long term debt.

Would you push your son, or daughter into a profession in the oil business after looking at this chart? Mr. Trump believes $40 WTI is too high.