Bankruptcy doesn't make assets -- such as factories, machines, contractual options to buy raw materials, workers' skills -- disappear. If markets still exist for products produced by these firms, Chapter 11 is the best way to discover this. Some workers might lose their jobs and some suppliers might lose their markets, but there would be no industry-wide collapse of the sort portrayed by the bailout's cheerleaders.
A government bailout of the Big Three keeps huge amounts of productive inputs in firms that can't use them efficiently. Forcing taxpayers to subsidize the continued employment of gargantuan quantities of raw materials, labor and capital goods in unproductive pursuits is a recipe for economic stagnation.