Americans are energy hogs. Our cars are too big. Our houses are too big. And, of course, our collective butts are too big, too. Aside from the last one, which can likely be verified with a tape measure, those claims are largely wrong. Over the past three decades or so, the United States has been as good as—or better than—nearly every other developed country on Earth at improving its energy efficiency. It has been among the best at reducing its carbon intensity, its energy intensity, and its per-capita energy use. And here’s the most important thing to remember when considering those facts: The United States has achieved these reductions without participating in the Kyoto Protocol (which would have set targets for reductions in carbon emissions) or creating an emissions trading system like the one employed in Europe. In fact, the United States has been better than nearly every other country on the planet at reducing its carbon intensity and its energy use without doing any of the things that environmental groups and renewable energy lobbyists contend are essential.