I agree it is a bad idea to grow corn to make alcohol. But it is possible for biofuel generation to be beneficial: the idea would not be to grow crops specifically for converting them to energy, but to use the waste and by products of existing crops.

For example rice crops in California's Central Valley have the rice plant (stalks/leaves) burned in the fields, which creates lots of air pollution. If that material could be used as a fuel or converted into liquid fuel we'd be solving two problems.

There is also the current practice of converting waste cooking oils into biodiesel-- restaurants and food processors are going to have waste oil, the only question is does it get thrown away or used as fuel?

Brian