Cash for clunkers did sell a lot of cars.
It's not far enough along in the buying cycle to have the true results of the house credit, but cash for clunkers didn't sell any more cars, it sold them sooner.
That's the correct conclusion. It also sold them with "rich people's" money (actually our children's and grandchildren's money, but that doesn't matter if their hearts are in the right place), and it sold them with lower manufacturer incentives because the government artificially supported the sales prices. In other words, it shifted my money and yours to GM and Chrysler and the UAW, and to a larger extent to Toyota/Honda.