I don't see it that way at all, at least from an environmental point of view. According to my calculations, the program saves 140 M gal gas/yr, worth about $530 M/yr. However, this represents only 0.14% of all gas used by Americans.
Assuming these new cars are kept for a total of 8 years (it takes 4 yrs just to pay off the carbon footprint of their manufacturing), then the program will save 1.7 Mmt/yr, what the country emits in 2.5 hours. And for that we're paying about $410/mt CO2, a huge amount ["mt" = metric ton] -- roughly 10 times the Waxman-Markey bill.
Christopher Knittel, a transportation expert at the Univ of California at Davis, calculated a value of about $500/ton, with a wide possible range.
A 9 mpg gain translates into annual savings of 3.8 million barrels of oil per year and nearly $1,000 for consumers at the pump -– not to mention that it will reduce carbon dioxide emissions by 660,000 metric tons a year. Okay, not a cost-effective emission reducer, but still, given the multiple benefits of the program, pretty darn good.How is this good? For all of us spending $3B, a small handful of Americans get a new car and savings of about $1000 a year in gasoline. The country will now use a grand total of 0.1% less gas. The environmental consequences are very, very small, and far overpriced at that.
This was an economic stimulus bill only, for auto dealers and those in the middle class who can afford to buy a new car with a trade-in. (This is the same middle class who by-and-large bitch about the size of government and its programs.)