The United States and Canada have a long history of shifting from one energy fad to the next—and sometimes back again—while rarely addressing the core issue of how much energy we use. As a result, the two nations have the dubious distinction of using twice as much energy per capita as the richest European nations and orders of magnitude more than most developing nations. The author argues that new energy sources such as renewables and new nuclear have no chance of proving up to the task unless we can curb our wasteful ways. Likewise, he argues that carbon sequestration and climate engineering will fall far short of heading off drastic changes in global climate unless we turn down the tap.
While not articulated in this manner within the article (which focuses on drawing out the policy implications rather than explaining the theory behind the analysis), Smil's analysis hinges on a theoretical accounting of the following chart showing the relationship between per capita energy use and the human development index for a variety of countries. The text accompanying the figure reads as follows: "At very low and low per capita consumption levels, higher use of energy is clearly tied to rising index of human development, but once energy per capita reaches about 150 gigajoules per year, the correlation breaks down. More is not better."
Crudely put, Smil is using the Human Development Index as a proxy for social complexity. Thus, consistent with the second law of thermodynamics, he notes the existence of a relationship between energy input and complexity -- the more complex a system is, the greater the energy input into the system necessary to compensate for entropy. But this does not imply that all social forms make maximal efficient use of that energy. Europe achieves a level of social complexity more or less equivalent with that of North America on half the energy input. For this reason, Smil argues that conservation rather than production or mitigation should be the focus of North American energy policy. But, as his survey of the current discourse surrounding energy policy in North America shows, conservation is not a major topic. Thus, while the article does an excellent job of diagnosing the current situation, it really doesn't come to grips with the path dependent nature of North America's form of social organization and level of social resistance associated with going down a different path.