The government’s Cash for Clunkers program officially begins today, but car dealers have been running ads like this one for a while already. They have to keep the public informed: Now you can trade in your old car and buy a brand-new SUV or pick-up truck with a hefty assist from Uncle Sam.

Here we have the government spending a billion dollars on about 250,000 vouchers for individual car buyers. Ostensibly, the purpose is to save some jobs and cut some emissions. Meanwhile, we’re in the middle of a budget crisis affecting transit agencies serving 22 million Americans. Green jobs and emissions-reducing transportation are on the line. When DOT Secretary LaHood holds his press event on Monday touting the roll-out of Cash for Clunkers, someone should ask him how the Obama administration can justify this dubious car industry subsidy while hanging transit riders out to dry.