Are environmentalists who want fossil-fuel divestment hypocrites if they don't adopt a radically reduced carbon lifestyle? That's a common charge among conservatives.

The United States has a long way to go before we get to U.K. levels of emissions. Some of this represents the fact that we have a lot of heavy manufacturing and we produce a fair amount of energy, both of which are very carbon-intensive.

But some of it is also our lifestyles, especially air travel, car travel, living in larger homes that we air-condition and heat to a year-round 70 degrees, and using a lot more energy-intensive devices, from computers and big televisions to refrigerators and clothes dryers.