Even though you see those buses spewing black smoke from the top, and even though a lot of them run with just a couple people some of the time, in just about every American city, if you net it out they are saving gas (and therefore emissions, which are directly proportional) by a factor of 15-20x.

It's a fact that 30-45% of traffic [1] in urban centers is caused by people cruising around looking for a parking spot. With more public transportation, not only do you reduce this traffic, you reduce regular traffic (less cars), and perhaps most importantly, you increase the economic productivity of the city since instead of erecting giant parking garages, they can erect giant office buildings and condo buildings - which, by the way, has the small added side effect of putting you closer to your job anyway since now you don't have to commute across five parking garages just to get to work.

Taxation and skewed incentives are bad, but let's be honest that's the reason why we have too many cars and roads to begin with. more public transportation in cities is a good thing.

The reason the suburbs blew up is because of skewed incentives. They blew up because everyone and their mother was able to take out a loan on a car they couldn't afford, and fill it with gas that costs half as much as what the rest of the world pays. It's not a good thing, and I'm not sure why you would try and argue that it is. Suburbs aren't where we ought to be and I'm happy to expand on why if you'd like.

Furthermore, electric vehicles and the like don't help the situation. If your car suddenly gets 60mpg instead of 20, it's only going to ENCOURAGE you to drive all the way across the state to get that special jar of peanut butter you like, instead of walking down the block to the corner store. as a result, we need to build more roads to get you to your precious peanut butter; and the new roads in turn invite more traffic, etc.

The solution is urban development with appropriate public transportation. Now, people hear the word "public" in public transportation and instantly think that it has to be funded by the government in an inefficient way. But I have been saying for a long time that that's absolutely not true. What we really mean to say is mass transit.

The New York subway system, which is one of the first and best subways in the world, were originally run by a couple of different private companies. Most cities in the world (outside the US) have free-market taxi systems that are 10x cheaper than what we pay here. and the private el trains and streetcars that used to be all over NYC before the government did away with them were even better.

Here's another interesting line of reasoning to chew on: banning cars in the city would go a long way to making public transportation more profitable for the city. think about it this way, the reason public buses need such huge subsidies to survive is because every person that rides a bus is freeing up space for someone else on the highway, actually making it MORE desirable for that other person to drive rather than ride the bus. but if you remove the option to drive, then you get around this problem and you don't have to pay extra (subsidy) for that person who looked out his window and saw that there was one less car on the road.

Also note that I'm taking about commuter-distance travel and less- intercity rail is a whole other story to go into.

If you live in a sprawl area like Tampa, naturally that's what you will think about, but Tampa is not the future. Tampa is a fine place, but it grew up as a result of bad policies and incentives. The future is cities like Shanghai, London, Hong Kong - these are the cities with the largest GDP growth over the last 25 years and projected for the next 25. Coincidentally, these are also the cities with the best mass transit- London is widely regarded as having the best bus, rail and metro system in the world; Shanghai has the longest and fastest-growing metro system in the world; and of course 90% of all daily journeys in Hong Kong are on public transport.

The smaller, newer cities that are "hot" in terms of growth are also mostly in China, and where there is no mass transit yet developed, bicycles are the main mode of transport.

The 20+ year historical trend of the US pop is towards urbanization, and that's not stopping. In 2000, 58% of the US pop [2] lived in cities of 200,000 or greater. The WORLD's population (yes, think of even the nearly one billion rural Chinese) is expected to be 70% urban [3] by 2050.

The future waits for no one!

Another note: We don't have to transplant people; it happens naturally. That's the power of markets. Just look at the changes in population of Detroit vs. New York over the last 20 years. See also The Great Migration [4]

[1] http://marginalrevolution.com/marginalrevolution/2010/08/par...
[2] http://www.fhwa.dot.gov/planning/census/cps2k.htm
[3] http://www.prb.org/Educators/TeachersGuides/HumanPopulation/...
[4] http://en.wikipedia.org/wiki/Great_Migration_%28African_Amer...