The number of registered vehicles in the United States hit a record 276 million last year, and sales of cars and trucks were steady, confirming that the huge drop in sales of a decade ago was attributable to a bad economy rather than a long-lasting shift away from “car culture.” Indeed, the four-wheeled population is growing faster than the human population in many dense cities with strong economies, including New York, Los Angeles, Chicago and Boston. This growth is mostly attributable to households’ buying second or third cars.

As they have been for over a century, cars are seen as a marker of prosperity, both as a measure of the national economy and as a symbol of personal success. It is disappointing that this cultural tradition continues despite the need to reduce greenhouse gas emissions, a leading cause of climate change. The total mileage logged by U.S. drivers is once again on the rise after a widely heralded decline during the last major recession, and the Census Bureau reported that 76.4 percent of U.S. workers drove alone to work in 2017, a slight increase from the previous year. The data suggests that Americans use their cars less only in times of abnormally high fuel prices or high unemployment. But our commitment to protecting the environment is worthless if we act upon it only when times are bad.

The four-wheeled population is growing faster than the human population in many dense cities with strong economies.

There are ways to make nonessential driving less attractive, even if federal and state governments are reluctant to use them. The federal gas tax, for example, has been frozen at 18.4 cents per gallon since 1993. Twenty states and the District of Columbia are more flexible, imposing additional per-gallon gas taxes that rise with inflation or with the price of fuel. But this may be getting things backward. Instead of adding to financial burdens when the price of gas goes up, it could make more sense to increase the tax when falling gas prices encourage people to drive more. There is also logic in including electric cars and other fuel-efficient vehicles in a tax scheme, since they reinforce the habit of driving everywhere.

Other policies worth consideration include taxes on mileage rather than fuel, with which Oregon is experimenting, using a measurement device affixed to cars; congestion pricing, or tolls on entering heavy-traffic areas where there is adequate public transit; and infrastructure improvements that allow for safe bicycling and walking.

Any policy aimed at reducing greenhouse emissions should be sensible enough to take into account the needs of rural areas and workers for whom driving long distances is part of everyday life. But recent job growth has been concentrated in large urban areas where solo driving is both wasteful and destructive to the environment. In these places, it is essential to discard the idea that prosperity means more and bigger cars on the road.

This article appears in February 4 2019.