I wonder if sugar cane has taken a beating bc/ it competes with corn syrup in this country. With the heavy corn subsidies, corn syrup is artificially cheap.  Maybe if corn were not so heavily subsidized farmers could grow sugar cane in the gulf area profitably.
i think you are right - get rid of all ag subsidies and let the grain mix change - we'd see less corn and lots more amaranth, switchgrass, etc.
the other subsidy that sugar has enjoyed is slave labor. Sugarland is also home to 4 units of the Texas Department of Corrections and the prison system not only operated its own farms but also rented the prisoners out to local plantations. American Sugar in south Florida imported Dominican and Haitian "guest workers" for the same purpose. Cuba had legal slavery until the 1870's and the Cuban workers from the fields were Castro's biggest supporters. Unless we plan to make semi-slaves and work them to death in the cane fields, sugar cane ethanol is a pipe dream.