The worst estimate I have heard is that it will increase unemployment by 2 million jobs. That assunmes that if the big three go under, none of the foreign companies building cars in the US will sell a single car nexr year. We lost one fourth of that amount last month, and the world didn't come to an end.
You have to factor in the ripple. The people who service the big 3. Suppliers and their suppliers, the people that cut hair, grocery stores service cars, ETC. The ripple will be devistating. Maybe you in another state will feel it maybe not. but in Michigan it will be a depression on top of a nation wide recession.