Hidden amongst all his rhetoric for war against Iraq, George Bush's state of the union address included a proposal for $1.2bn to research hydrogen as an alternative car fuel. A development programme is meant to make such cars feasible by 2020.
Part of the reason for the project was meant to be reducing US dependence on oil, but funds included $19.6m for generating hydrogen from gasoline. This was criticised as "running to McDonalds to get fit" Other critics pointed out that even if gasoline wasn't the source, generating hydrogen requires more energy than you get out of it.
This might be OK if you could use renewable energy such as wind, wave, tidal and solar power to generate the hydrogen for cars. However, renewable energy has technical limitations and environmental impacts.
If crops (eg. sunflower oil) were used to power the US's cars, it would take four times as much land as is now farmed for food. Renewable energy could not possibly power the 700 million motor vehicles currently on the world's roads, let alone the 2 billion vehicles required to allow everyone "equal access to cars".
Renewable energy hardly features in Bush's energy plan. His priorities include "securing oil supplies" and more coal and nuclear power stations, so the hydrogen for cars would come from fossil or radioactive fuels.
Bush's proposal is a smokescreen to hide