B. docile_body
Before the 1950s, though, there were a lot of other auto makers: Pierce-Arrow, Nash, Premier Motor Corporation, Essex Motors [Detroit], etc. The 1950s may have represented the culimination of US automaker monopolization. But before that, there were definitely more than just a 'big three.' It was a very active, lively market within the US.
I happen to have a book in front of me that contains alot of ads from US auto-makers from the 1940s and prior, going back to about 1890. You'd be amazed how many there were.
-B.
^^^^^ CB: Yea, the idea is it is a process, which means ebb and flow and a tendency. The idea is not a build up to some monopoly companies that last for all times.
In the case of auto, the initial historical process culminated in the Big Three. Then with the rise of the Japanese and European companies to compete with these ( for the wellknown reason of the remix of the world capitalist economy after the intercapitalist rivalry resulted in the creative destruction of WWII). Of course, the Japanese and European companies are monopolies too, confirming rather than contradicting the principle of tendency to monopolies.
And Daimler merged with Chrysler. So make that nine instead of ten, a monopoly direction tick on the counter in all this.
As you point out, compared to its beginning, the world auto industry is still relatively monopolized , even with the entry of new monopolies due to other world capitalist processes.