The number of new cars needed per year in America will not change. It is not economical to scale up overseas manufacturing and import all those cars ... especially when U.S. plants can be bought cheaply. Manufacturing workers and parts suppliers here won't lose their jobs. If Japanese and German companies buy the plants, they could retool them for their own (proven profitable) designs or continue to build selected U.S. designs. They would probably do some of each, retooling only the plants that have been building cars they choose to discontinue. The parts suppliers must follow suit either way.
So I say let the big 3 go bankrupt. Let their stock become worthless - anyone who's been betting it would have value deserves to lose. Let their pensions be taken over by the government. Let them renegotiate union contracts - the unions know what the risks are now. Let them stop building old makes without penalty from their dealer networks - Toyota has only three (Toyota, Lexus, Scion) and nobody misses Plymouth. Let them eliminate redundant marketing costs for essentially identical vehicles. Make them fire their management. The new management should be drawn from other industries.
I like cars. Of the dozens of models built by the Big 3, I can think of only one that I wouldn't sell if the keys were handed to me. I'm hoping for a new era in the American auto industry, one that begins by admitting to a vast failure. The average car on the road will be safer, more reliable, and cheaper. I don't know what it will be called, and I don't know where the profits will go, but I know it will be made in America.