A critic of cyclists and cycling recently wrote the following:
What's going to be your argument when, as is beginning to happen now, motor vehicle engines no longer run on fossil fuels and don't pollute the air?
This provides an excellent example of an abiding problem in political discourse: achievements in the future tense. Will we have non-polluting cars someday? We do not know, but we certainly do not have them (in any numbers) now.
GM can produce electric cars, but we don't know they can produce enough to really make a difference. Nor do we know if we can grow enough energy crops to power millions of automobiles. We have yet to reconcile the desire of the rich for luxurious mobility and the basic needs of the poor: energy crops compete with food crops for farmland, and electric cars bid up the cost of electricity for heating and cooking. The engineers have some work to do before a truly environmentally friendly automobile reaches the showroom floor.
If it does? Some of us will sigh with relief and take the car. Some of us will insist on riding our bicycles for pleasure and health. But we ought not to base our individual or collective decisions about transport today on some imagined future. Today, when we choose to drive or ride, and when we choose to build bike paths or roads, cars pollute.