Both Japan and Detroit can make a good car if they really want to. I personally would rather buy American if the quality and price are comparable for the most part but it is not the first thing I look for. Buying a domestic product that is inferior just makes you a large banana republic.
As I said elsewhere, Toyota in my opinion makes the best fork lift in the world. I personally don't buy fork lifts, few individuals do, but the North American competition is not as good at least in the size class of lift truck I have experience with. US lift trucks have US industrial engines made from patterns and core boxes made in the '50s and they no longer cut the muster.
I don't feel Japanese cars are necessarily better any more. But GM can't blame its problems on anyone else, it has failed to produce a first rate product on a cost effective basis for a long time. Yes, the Corvette is a great value for a car in its class-in fact probably too good, you don't buy an expensive sports car for cost-effectiveness! Yes, the Duramax is great. Yes, the Northstar is first class tech. But overall their lines are stodgy, middle-of-the-road, and have no compelling reason to buy.
DCX has done good things with Jeep and will probably do more, but I don't think they really have a strong idea where they want to go in a way the American Jeep buyer will really go for.