There's nothing inherently dense about American "coastal cities". In the U.S., density is primarily related to age--how large a city was prior to the invention

There's nothing inherently dense about American "coastal cities". In the U.S., density is primarily related to age--how large a city was prior to the invention of the automobile. With the exception of the oldest cities in the north east, most U.S. coastal cities are not particularly dense unless they are also quite old. LA is a prime example.