...because we were doing it wrong? Obviously we should have given up on space exploration because chemical rockets are so inefficient.
Corn and ethanol are used because the people who stand to profit from them have significant political sway, not because they make any sense whatsoever to do. It's too soon to give up on biofuels. Energy crops should be part of an integrated agricultural solution. The idea that not growing crops for fuel means energy production won't increase food prices is ridiculous. Energy is a large part of what we pay for when we buy food. Fertilizer, pesticides, farm machinery, and distribution. What we do need are incentives to put idle agricultural land back into production before using forested land. Also, around me a fair amount of land is still used to grow tobacco. Only good can come from repurposing that.