Illustration by Gary Hovland

Often used to help emerging industries grow and prosper, subsidies can be a valuable tool for governments. In 1979, the Carter administration began to subsidize corn ethanol for two reasons: the oil crisis had spurred the search for alternative fuels, and farmers needed new markets to absorb record corn surpluses.

Farmers and ethanol blenders benefit from three different forms of support: tariffs on imported ethanol; the federal renewable fuel standard (RFS), which mandates a rising volume of corn ethanol in gasoline; and, most important, a tax break known as the Volumetric Ethanol Excise Tax Credit, or VEETC.

Subsidies should become unnecessary when an industry is mature, but the lucrative corn ethanol industry has treated them as a permanent entitlement. VEETC -- which cost taxpayers $6 billion last year -- is set to expire at the end of 2011, and an unlikely coalition of opponents, in which greens and social justice activists find themselves aligned with Tea Party loyalists and the fast food industry, is now hoping to kill it for good.

Click on MORE PHOTOS above to see who would benefit from keeping the ethanol subsidy alive and the array of strange bedfellows working to end it.

UPDATE 6/16/2011: The U.S. Senate has voted overwhelming to end the corn ethanol tax credit as part of a larger bill (which must still be approved). Read more from NRDC.