In Canada, we sold a lot of Dodge Colts etc. Our fuel prices have been high for many years. In Canada, the best selling vehicle is the Honda Civic followed by many other compacts and sub compacts. Once the price of oil goes up again, and it will, it is likely that US demand for small cars will look similar to ours.
My prediction is that the Ford Fiesta is going to be a huge hit in N America for this reason. Chrysler and GM currently do not have anything N American made that will be competitive coming down the pipe. Chrysler needs this technology and Fiat needs access to Chrysler's distribution network.
If we loose the Detroit 3, and a good chunk of manufacturing in N America as a result, we are going be doing nothing but serving hamburgers to each other. Assuming we have the funds to pay for them.