Chuck, your idea of the government eventually saying what car you can but is ludicrous and totally knee-jerk reactionary! The idea that the government would make you buy a certain car is much more in favor of right wing ideals than left wing. As a matter of fact it's exactly the idea that right wingers like, letting private interests influence public policy. It's pretty much the standard definition of the dreaded "F" word that the right wing is often associated with.
Actually, the federal government already tells you what kind of car you can buy. Sure, they don't say, you must buy GM (although the bail out of the UAW -- ahem, I mean GM -- was a roundabout way of taking my money to allow other people to buy cars from people who happen to be favored by the party that controlled the government at the time), but they say, all new cars must have a rear view camera (at an extra cost of a few hundred dollars to the purchaser), that they must meet certain fuel efficiency requirements, etc.
I also have no idea what you're talking about "private interests influencing public policy". That's what voting is. For example, public employee union members don't seem to get it, but it's the private sector taxpayers that pay the salaries of public employees, not just the Koch brothers or the monopoly man. I have decided that I want to get the best price possible for their services and not pay for superfluous positions like guidance counselors for elementary school students. Should I find that education is worse off for it, then maybe I'll change my mind later. Either way, I'm voting in accordance with my own private interests. But I don't know, maybe you've found group of all wise, all knowing central planners that have the answer to all those questions.