Matthew Yglesias points to an interesting study on world subway systems.

It’s just a bunch of maps printed out at the same scale, and you notice a difference between the US and the rest of the world:

Take a look:

London

New York

Tokyo

Moscow

Paris

Chicago

Berlin

Washington, DC

Osaka

San Francisco’s BART

Boston

Philadelphia

There some outliers in the rest of the world, Seoul, for example, but the difference, except in New York, is that America does not really build subways, which serve the city and allow you to get around in the city, it builds some sort of light rail, for commuters to get into the city, in yet another subsidy of the American suburb.