This post was excerpted a post written for Grist by Terry Tamminen is the former secretary of the California Environmental Protection Agency and is now a policy adviser and author. His latest book is Lives Per Gallon: The True Cost of our Oil Addiction. In the past few weeks, how many of us have seen (or participated in) that summer staple, the three-legged race? Two people stand side by side, each placing one leg into a gunny sack, then trying to coordinate movements to stay upright while running to a picnic table at the finish line. Visualize the U.S. and China similarly tethered together, but each trying to beat the other to a prize more valuable than hot dogs and potato salad -- economic dominance in the 21st century. The two superpowers are clearly joined at the hip economically, because so much of China's production is shipped to U.S. consumers. Although each nation may have one leg apiece this common sack, make no mistake, they are competing to get ahead in at least one crucial area -- to be the most energy-efficient, because energy resources enable economic growth and using those resources efficiently drives higher profits, employment, and tax revenues. Click here to read Tamminen's full article.