The U.S. dependence on fossil fuels became painfully apparent during the 1973–1974 oil embargo by the Organization of Petroleum Exporting Countries (OPEC). Even though the actual reduction in oil supply was only about 10%, the resulting social and economic disruption influenced U.S. foreign policy for at least the next 40 years. The development of shale gas and tight oil in the twenty-first century using horizontal drilling and hydraulic fracturing was the direct result of the embargo. By 2019, the U.S. was producing more oil than Saudi Arabia, and more gas than Russia. The abundant natural gas from shale led many electric utilities to convert power plants from coal to natural gas. Coal use suffered as a result, with the coal companies claiming it was due to a USEPA “war on coal.” The truth is that gas is cheaper, much cleaner, and almost 50% more efficient at generating electricity. The vast majority of electricity in the United States is currently produced from fossil fuel combustion, and fossil fuel powers nearly all vehicles. Eliminating our dependence on fossil energy to combat climate change will be a massive and disruptive undertaking.