Every marginal increase in gasoline use is...
from imported oil,
from difficult expensive and dirty oil,
often sent in massive ships burning incredibly dirty bunker fuel, expanding the wealth and economies of countries that hate our way of life.
Since E85 has already "ramped" to 13 billion gallons, to conclude that there is no counter argument, I would have to assume that more foreign oil exploration, extraction and importation is better for the environment.