There has been considerable discussion about the extent to which motor-vehicle use in the US is "subsidized," making petroleum-based motor vehicle use more attractive than other transportation modes. Estimates of these subsidies vary widely, and in many cases can be criticized on methodological...

Analyses of the full social cost of motor vehicle use in the US often estimate an "oil import premium" that includes the military cost of defending oil supplies from the Persian Gulf. Estimates of this cost have ranged from essentially zero to upwards of a $1 per gallon (about $0.25 per liter)....