Should the United States raise CAFE standards for cars, even if it means a loss of jobs and a poorer economy?

CAFE (Corporate Average Fuel Efficiency) dictates that American-made cars have an average miles per gallon that meets a government-mandated level. If they don't, they are given a huge fine. Obviously raising the CAFE standard would help conserve fuel and reduce air pollution. However, it could also put many people out of work and have a negative impact on the economy.