Tverberg's analysis nails it. Worth reading all the way through. The themes that have been discussed on these forums over recent years are accelerating and converging.
Oil Price Slide - No good way out (Our finite world, 5th November 2014)But the issue at hand is really diminishing returns. Prior to diminishing returns becoming a problem, it was possible to extract and refine oil cheaply. With cheap oil, it was possible to create an economy with low-priced oil, inexpensive infrastructure built with that low-priced oil, and factories built with low-priced oil. Workers seemed to be very productive in such a setting, in part because low-priced oil allowed increased mechanization of production and allowed cheap transport of goods.
Once diminishing returns set in, oil became increasingly expensive to extract, because we needed to use more resources to obtain oil that was very deep, or in shale formations, or that required desalination plants to support the population. Once we needed to allocate resources for these endeavors, fewer resources were available for more general uses. With fewer resources for general activities, economic growth has become inhibited. This has tended to lead to fewer jobs, especially good-paying jobs. It also makes debt harder to repay. History shows that many economies have collapsed because of diminishing returns.