$2.00 for a gallon of gasoline may seem like a towering, ominous threshold, but the fact is, it’s a threshold we passed long ago—we just didn’t notice.
By the time you’ve factored in tax subsidies (to those charming oil companies), program subsidies (e.g., fed/state costs to improve transportation infrastructure plus R&D, etc.), protection subsidies (that would be military costs—amazingly, one of the lesser factors), environmental/social costs (e.g., localized air pollution, water pollution, noise pollution, global warming, etc.), and other external factors (costs of increased traffic congestion, car accidents, and subsidized parking to name a few), the actual cost of a gallon of gasoline is somewhere beteen $5.60 and $15.14.
(via International Center for Technology Assessment: “The Real Price of Gasoline” [PDF]; the ‘executive summary,’ which provides a cursory overview of these external costs, is available here)