The US farmer produces over 12 billion bushel of #2 yellow field corn every year. Humans eat sweet corn. Humans do not eat this field corn. It is fed to livestock. Extracting Ethanol from this corn only uses the starch of the corn. All the protein remains as Distiller Dried Grains (DDG) animal feed. Protein is what builds muscles in animals. Muscles = Meat, Steak, Hamburger, etc. Corn starch created methane gas in farm animals. This is smelly & is 15 times stronger of a greenhouse gas than (CO2) Carbon Dioxide ever was.
If you converted all the Corn grown in the USA into Ethanol it still leaves US & the World nearly all the animal feed value in the form of DDGs that we would have got from feeding corn directly to animals. We still export the DDG animal feed to China & the rest of the world the same way we did the corn.
If you converted all the Corn grown in the USA into Ethanol it can replace 25% of the total US Gasoline demand 12% of the total US Crude Oil demand.
Mixing Ethanol into Gasoline prevents the need for refineries to add the ground water polluting MTBE into gasoline.
Ethanol production in the USA has created over 500,000 good paying jobs in the USA. Not part time minimum wage jobs. If you add up the 45 cent per gallon of ethanol tax break the oil companies get it is around $3.6 billion per year. Divide that by the 500,000 good paying jobs it created & it is about $7,000 per job. Way less than any other green job.
The Brazil ethanol tariff was only to offset their tariff on our ethanol going to their country. It did not cost us a dime & created no revenue. Brazil just dropped their tariff a few months ago & we may soon drop ours but Brazil heavily subsidizes their ethanol industry & would try to dump their subsidized ethanol onto our markets collapsing our ethanol industry. Brazil & many other countries now import our US Corn Ethanol into their countries.
E10 gasoline is what we all burn in our automobiles in the USA today. It is 10% ethanol. That 45 cent per gallon of 100% ethanol is divided by 10 for E10 gasoline. That equals a 4.5 cent tax break for oil companies who sell you E10 gasoline. If this tax break is taken away you will have to pay 4.5 cents per gallon more at the pump for regular E10 gasoline.
You pay ~12 cents per gallon credit/debit card transaction fee per gallon just so you don't have to mess with cash.