The future of car design could be changed by the signing of a bill in California. In what its supporters claim is the most significant environmental step in the US motor industry in two decades, the new law would regulate emissions of greenhouse gases that cause global warming.
The car and oil industries are already mobilising fierce opposition, warning of "social engineering" that could lead to more road deaths, higher taxes and fuel costs, and the outlawing of the popular 4x4 sport utility vehicles (SUV) which have been called some of the worst polluters.
Governor Gray Davis, a Democrat who is standing for re-election this November, has about a week to decide whether or not to sign the bill, which was passed by both the state Senate and House of Representatives. Already under pressure from the car industry, unions and the business world, Davis knows that, if he does not sign the bill, he will lose the vital support of the environment movement and liberal Hollywood.
California's 23 million vehicles cause 58 per cent of the greenhouse gas pollution in the state - compared to 31 per cent in the rest of the US. The bill is backed by some political big hitters, including potential Democrat presidential candidates Joe Lieberman and John Kerry and the Republican senator John McCain. Actor Paul Newman also campaigned for the bill along with much of Hollywood. The Green movement sees it as a powerful rebuff to President Bush's refusal to sign the Kyoto protocol, which commits rich countries to reducing emissions. The US is responsible for 24 per cent of the world's man-made carbon emissions.
The bill directs the state's air resources board to introduce regulations to achieve "the maximum feasible reduction of greenhouse gases" by 2005. These standards would then have to apply to every new car sold in the state from 2009.
As California has the world's fifth-largest economy and represents 10 per cent of the American car market, it could mean that US manufacturers will have to start making environmentally friendly cars within seven years.
Japanese car manufacturers, in particular Honda, are already anticipating eventual moves to such cars, but American makers had assumed that the election of Mr Bush guaranteed that there would be no immediate pressure on car emissions. Now that could all change and with it the shape of cars as designers seek to incorporate fuel-saving engineering.
The coalition fighting the bill includes the car and oil industries and their related unions.