Does anyone know the pollution emitted by aircraft per passenger-mile? I would think it is many times that emitted by the automobile. Yet I never hear environmental groups kick up any fuss about aircraft. Greenhouse emissions (CO2) must be much higher with aircraft. Besides, in the larger scheme of things, the average person going to work or shopping seems to me a more necessary function than someone flying to a vacation spot. IMO we need to tax jet fuel a lot more and apply that money towards reducing the overall tax burden on the average working family.