Before the USA slides into its economic funk and the price of oil slides all the way back again, I really do hope that the people of China and India realize that the problem with allowing cars to overrun cities goes well beyond problems of carbon dioxide pollution - and base their city infrastructures on other transportation modes. But then again, it is as much a problem with the first world investors in these industries in China and India - bringing the same problems to these countries.
The discussion should be more about:
Huge cost in road deaths
Huge cost in road injuries
Loss of space for people
Noise and nuisance
Lack of human interaction and social fabric
All the other environmental costs other than CO2 (tyres, oil, plastics)
Environmental cost of producing these vehicles and the materials that go into them - not just running them
Anything else ? I am sure there are more reasons why cars just don't work as the primary transport system for cities ...