Turns out I was wrong – it looks like taxes make up most (if not all) of the price difference of gasoline between the US and the EU. Here are a couple interesting charts.
Something that I find interesting is that the high price of gasoline seems to push consumers towards fuel efficient cars, though its hard to tell for certain since there is so much (over) regulation involved. Also of note is that all that extra efficiency is completely lost to the government through obscenely high taxes. So even though our cars don’t have nearly the economy that European cars do, we get much more bang for the buck.