THE EUROZONE DEBT CRISIS, risk, and regulators. “One possible story about the financial crisis is that an unusually rosy period of growth in the west taught us to expect–no, to need–an unsustainably high rate of low-risk return on assets. We made a whole lot of unsustainable promises during the boom years, most of them involving permanent increases in the ratio of non-workers to workers. Those promises required a very steady cash flow, but also (because of demographics) a very high rate of return.”