Many factors at work
Yes, interest rates, global macroeconomic issues and many other factors have played important roles in the big picture I outlined, but I wanted to tell a simplified story (which was long enough already). I do not claim that energy is the only factor, and it's difficult to tease out the role that energy has played independently of everything else. But it should be obvious that one cannot generate a single dollar of GDP without consuming energy, and that all of our economic activity up through 2004 was generated in an era of cheap energy that is now behind us, which has radical implications for the overhang of debt. Unfortunately, textbook economics treats energy as an infinite, external input that is infinitely substitutable, when it is not.
