There is a very vital need for urban areas to promote public transportation for all kinds of reasons--no traffic jams, less fuel being consumed, less vehicle emissions, fewer accidents, less daily wear and tear on personal vehicles, less need for parking spaces, etc..
Owning a car in other countries is a bit of a luxury, so public transportation is far more common. In the U.S., with our emphasis on "rugged individualism", automobiles are like an "ego-thing". As U.S. cities have expanded, the various local governments are trying to encourage residents to use public transportation more frequently. In large eastern cities it has been the norm. Elsewhere, not so much so.