Salience, or voting as if the environment matters: the path to a green energy future and a stable climate is clearer than ever--but we do need to start voting to put ourselves on it.

• Author: Young, John E.

The professor who taught my college introductory political science course greatly emphasized a dry little word: salience--a measure of how much people's opinions on a given subject actually influence how they vote. Issues that are immediate or the subject of great passion, such as one's job, or religious freedom, usually have high voter salience.

In the United States in the 1980s, the global environment was the definitive low-salience issue. Everyone, it seemed, agreed that the environment should be protected, but politicians did little. They got elected to address more immediate concerns, such as tax cuts. Studying global sustainability at that time was both extraordinarily exciting and extremely frustrating, because so little public attention was focused on huge problems like fossil-fuel use and the specter of global warming, the AIDS epidemic, deforestation, the global extinction crisis, and the threat of more nuclear accidents in the wake of Chernobyl. I think my Worldwatch colleagues and I sometimes felt that we were shouting into the wind.

When I arrived at Worldwatch Institute in January 1988--on the day the first issue of this magazine came out--gasoline cost about $1.46 per gallon in the United States (in today's dollars), the average car or light truck got about 22 miles per gallon (9.4 km/liter), and Americans drove about 2 trillion miles (3.2 trillion km) a year. Since then, the Berlin Wall has fallen, the Internet has transformed global communications and markets, world population is up by 1.5 billion, and the global climate is warmer by about a third of a degree Celsius.

Some things, however, seem very much the same. The U.S. government is split between a conservative Republican president and a Democratic Congress. The president opposes most environmental initiatives and is closely allied to the energy industry. A presidential campaign is picking up speed but the candidates are paying little attention to environmental issues. Oil remains the lifeblood of the American economy and the average car or light truck gets about 21 miles to the gallon (8.9 km/liter). Gasoline prices have risen, but Americans are driving roughly a trillion more miles (1.6 trillion km) each year.

Blame American energy policy, which is basically to keep energy cheap no matter what the cost. Cheap oil in the 1980s and 1990s made it logical for millions of Americans to buy SUVs and move to remote suburbs, and suburban sprawl is the primary factor behind the...