Why do you think U.S. sugar cane is $2.40 per gallon whereas Brazil'a sugar cane is 81 cents?
Because we are subsidizing and supporting a huge alternative sugar industry, namely beets. The amount of land in the United States suitable for growing cane sugar is small compared to the demand. Cane sugar also produces a higher quality and yield of sugar versus beets. But beets have been a boon to the economies of areas subsidized to grow them and they well not easily go away.
Likewise, your two year old figures on corn convesation costs are much higher now, but these subsidies are not going to go away quietly either.
The rich no-drill greenie weenies in San Fransicko, New Yawk and Seattle have common ground with the sugar beet farmers in North Dakota and corn growers in Iowa on this issue.
You should not forget about corn farmers in the sugar subsidy madness. Tariffs on imported sugar mean corn syrup will be the substitute. I think that the corn lobby is the unnamed co-conspirator in the sugar subsidy madness.