Last year, Congress passed an ethanol mandate which mandates that drivers use 7.5 billion gallons of ethanol annyally by 2012.
That requirement ... is currently increasing the cost of gas, since ethanol is in short supply.
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...The U.S. currently levies a tariff of 2.5%, as well as a second duty of 54-cents-a-gallon, on all ethanol. That equals a giant tax that must be factored into already sky-high gas prices, and helps explain why the import market remains tiny.