In absolute numbers it is peanuts. GM sells over 6 million vehicles globally every year, and $2.8 billion is nothing when you’re running a deficit of $1.4 trillion. And my statement that it “went a long way towards stimulating Japan’s economy” was a commentary on the fact that it did bupkis for ours. Even under the best, most rosy scenario you can concoct in the aftermath of Cars For Clunkers, all you can say is that hey, Japan did well. GM did OK, Ford less so, and Chrysler’s sales were hideously bad. The program certainly didn’t keep the money home, and no automaker was clamoring to open any new factories to keep up with the artificially induced rise in demand. They’re already over capacity.
Oh, well then, never mind. I don’t know what sort of environmental impact it had but I agree that dollar for dollar its probably not the best way to celan up the environment. As bad as these clunkers were, they still need to pass emmissions tests so there is a cap on how bad any of them were.
Maybe not quite. It appears that only 33 states require emissions testing (link) if I’ve counted correctly.
And even that number is a bit deceptive. Ohio is listed as requiring emissions testing, for example, but actually only seven Ohio counties require it. If you live in one of the other 81 counties in Ohio, you’re good to go, regardless of how much crap your car is spewing into the air.
And as long as those companies remain profitable in the US they’ll continue to hire American employees, purchase American equipment and award business to American suppliers.
And there are situations such as we have here in Texas. If your car won’t pass the emissions test, and (iirc) you spend $1500 trying to get it to pass, you can get a waiver.
Still, it probably wasn’t the most cost effective way to curb pollution, and sent some old collectible cars to the crusher that otherwise wouldn’t have gone. 
The main purpose of CfC was to get rid of the large inventory overhang from the recession. They of course required the new cars to be fuel efficient, but that was a side benefit, not the main goal. This inventory was owned by the car dealers, not the car companies, so unless you think all Toyota dealers are Japanese citizens, it helped the good old US of A quite a bit also. Certainly US manufacturers didn’t seem to complain.
Another benefit was that it got people back to the car dealers, who were feeling kind of lonely at the time. And who knows, maybe the good sales of fuel efficient Japanese cars helped the US car companies actually be convinced to market fuel efficient cars with a bit more vigor.
It was just one of many factors which led to GM now being number 1 - and who thought that was going to happen a few years ago?
As for valuable old iron being destroyed, the amount paid for clunkers was small enough that anyone stupid enough to trade in a valuable classic would probably have scrapped it anyhow.
It’s true. they were lonely. I bought a car around this time. It was the only time I’ve ever felt that I could almost dictate what I thought was fair to pay for the car.
I didn’t mean to imply that people were crushing '56 Thunderbirds. However, the example in a news article I read on the procedure for disabling a CfC trade in was a large displacement, late '90’s 5 series BMW. I think it’s cars like that which will be rarer than it would have been without the CfC program: large displacement cars that wouldn’t have been old enough to be collectable when the program ran.
For example, here’s it happening to a C4 Vette: http://jalopnik.com/5337431/make-the-pain-stop-corvette-gets-clunked
On the other hand, those Japanese companies keep a substantial number of my neighbors employed due to local factories whereas none of the US car companies provide jobs around here. Those peoples’ paychecks help keep our local economy tottering along.
Buy “American” and keep Mexicans and Koreans employed.
Buy “Japanese” and keep your American neighbors employed.
Actually, I’m in favor of jobs for everyone, but I can’t help but notice that locally the foreigners employ more of my neighbors than the American car companies do.
Anyone who thinks a fourth generation Corvette is “collectible” (other than a ZR-1) ought to be tossed in the crusher themselves.
Hey, I’m not here to judge. People collect Ramblers.
Similarly, Illinois has emissions testing, but only in metro Chicago, and in the counties in SW Illinois which are near St. Louis.