Lessons from the Second City
To a person from Atlanta, public transportation means: riding a train that hardly takes you anywhere you want to go; paying too much for a ride; riding with some less-than-desirables; and only riding if driving is absolutely out of the question.
As far as I can tell, to a person from Chicago, public transportation means: riding a train that takes you to the front door of any place in town, even to the suburbs; paying a decent amount for a ride; riding with a healthy slice of the Chicago socio-economic spectrum; and riding anytime you want to go somewhere.
Why? There are many reasons, but the primary one that I can tell is that Chicago is very dense, whereas Atlanta is famously spread-out. This difference, by the way, explains other interesting features about Chicago, such as its ample supply of tall buildings. A moderately large building in Atlanta could get lost in Chicago. But a public transit system that works needs lots of passengers in not-so-many miles. Bad news for Atlanta planners, unless they can figure out a way to give Atlanta a natural boundary to bunch up against such as Lake Michigan, New York harbor, or a nice big mountain.
It should come as no surprise that an "L" system that actually provides good service would have its origins in private ownership. From the founding of the first "L" line in 1888 until 1947, the many lines were privately owned and funded. Not only was a public goods problem solved by these private lines, it was solved very well, not just adequately. The story of how these lines eventually became part of the public CTA is a long one, but suffice to say it's rife with government interaction, and that the rail systems, for some reason, were unprofitable after the Great Depression and wartime rationing. The system, though no longer private, clearly demonstrates, in its early success, the problem-solving capabilities of private enterprise.
Compare this with Atlanta. The MARTA, as the rail system is called here, has a North-South line with a fork at the top, and an East-West line with a one-station branch to the Northwest. In 1971 the newly-formed Marta agreed to take over (for about $13 million) Atlanta's private bus system, and already began applying for federal aid. In 1972 it reduced bus fare from 40? to 15? (so far so good) but began receiving sales tax funding from the metro area. [It seems likely that the reduction was to encourage people to ride to demonstrate the need for public transit, but that is just a guess.] The early years were full of government grants and tax payments to the system. Not only was it funded through what amounts to extortion, as opposed to Chicago's system, but it also had eminent domain, which meant that some people who lacked sufficient political or legal sway were sacrificed to Atlanta's dreams of mass transit.
Fast forward to the present, with the conditions I gave you at the beginning. Marta has budget crises left and right. Huge amounts of its funding come from taxes, not through user fees. Atlanta has some of the worst traffic in the country, and still people prefer to drive rather than use Marta. Without continuous payments from the government, with money taken from Atlanta residents, the system would collapse.
These two cases indicate something very important for city planners. First, if a city demands mass transit, private enterprise will supply it. Second, if a city does not demand mass transit, building it anyway (publicly, since private enterprise does not supply what is not demanded) will result in a system so poor that few people want to ride it and that can only survive on continuous 11th-hour rescues with tax dollars. Either way, we will get from point A to point B without you.