The things to consider with European diesel cars - They measure mileage with imperial gallons, while we use US gallons. That is a 20% penalty right off the top. European crash standards usually aren't up to US ones, so they get a lighter car. With 60 million people in a land area the size of Oregon, most everything is 'in town' driving. A US version of the same car would have a fuel penalty associated with the weight of extra safety features. We want to survive an 80 mph interstate crash! The last diesel price I saw around here was ~15% more than gasoline, so again, a cost penalty. So figure 20% 'mpg' conversion penalty, ~10% weight penalty and 15% cost of diesel penalty, and suddenly that 60 mpg European diesel is roughly equivalent to a ~35 mpg American gasoline car.