The Iron Law of Oligarchy At Work

There were 272 automobile companies in 1909. Through consolidation and failure, three emerged on top, two of which went bankrupt. Spotting a promising trend and a winning investment are two different things.

From here.

I would observe, however, that this is a list of American automobile companies.  There are many "foreign" automobile companies out there selling cars in the U.S. market and maintaining the oligopoly to which markets seem to naturally trend. The Iron Law of Oligarchy is hard at work, however, with more than fifteen different companies selling cars to U.S. customers.  

One of the "Big Three" is now a subsidiary of Italian automaker Fiat, rather than an American automobile company. General Motors went bankrupt and has since reorganized. Ford didn't.  On the other hand, Tesla has come into its own as a new American automobile company.  Also, Harley Davidson is an American company selling motorcycles in the U.S., and General Dynamics manufacturers and sells wheeled military vehicles in the U.S.

Many of them (Hyundai, Honda, Toyota, Nissan, Volkswagen, BMW, Mercedes, Mitsubishi, Mazda, Kia, Subaru and Fiat-Chrysler) have manufacturing operations in the North America and significant numbers of U.S. debt and/or equity investors.

A few more foreign automobile companies sell cars in the U.S. but do not have plants in the U.S. (e.g. Porsche and Rolls-Royce).