Suburban flight in the US didn't occur until long after cars became ubiquitous. People had the means to move to suburbs for years but didn't do so en masse until the urban cores started to rot.
People moved out of cities when they became shitholes, and people stay out of cities out of a perception that they are shitholes. Said perception may be true or false depending on where you are.
There is also the issue that for people with families, many urban centers have in the past few decades reconstituted and cleaned up, but without the infrastructure that families are looking for: e.g., schools.
Suburban living is all about being safe from criminal hordes outside the gates - whether real or imagined.
It seems you're not acquainted with the concept of "streetcar suburbs" [1]. The Wikipedia article goes into some detail; I recommend it for the curious who'd like to know how streetcar technology drove suburbanization before 1920.
FTA: "Because streetcar operators offered low fares and free transfers, commuting was finally affordable to nearly everyone."
This is not academic information about the distant past that no longer applies. Transit-oriented development [2] is impacting our cities positively today. It will be a long time before driverless cars have an impact.
1: http://en.wikipedia.org/wiki/Streetcar_suburb
2: http://en.wikipedia.org/wiki/Transit-oriented_development
And that's part of the point exactly - before suburban flight the concept of "suburbia" was transit-aligned, grid-based, focused around walkable distances and small(ish) housing. People were fine living in these places, even long after cars became ubiquitous. The modern suburb was not born until the collapse of urban centers.
Today we understand all of the above as "urban". The bulk of the American population lives in the modern incarnation of suburbs, not the 1920s version of it. Still-extant streetcar suburbs are now sold more as urban neighborhoods than not.
The modern suburb calls for large houses, even larger lawns, and subdivision-style street layouts (with an unspoken design intent of keeping out undesirables, a core part of its history and continued appeal). Map[1] is a modern suburb, full of meandering streets, deadends, cul-de-sacs, and indirection - and that's what I was referring to, considering that modern suburbs such as this grossly outnumber streetcar-urban neighborhoods in the US today.
If you took someone from a typical suburban environment in the US and dropped them in a streetcar suburb they'd perceive it as distinctly urban.
Look at it from a different perspective. Why is it that in Europe more of the population of the various metro areas lives in the city than in the surrounding suburbs, as compared to the U.S.? Do Americans just inherently like big houses and large lawns more than Europeans? And if they do, why didn't they move out of the city long before 1960, when it was eminently practical to do so?
That of course doesn't mean that suburbanites are racist today. After decades of suburban exodus the core cities are shells of their former selves, urban public school districts are almost exclusively for the poor, etc. There's lots of non-racist reasons, today, to not want to live in the city besides the inherent availability of lawns, etc. But given how racist society as a whole was in 1960, I think it's ridiculous to claim that the racial tension precipitated by the civil rights movement and desegregation didn't play a large role in tipping the balance between the cities and suburbs.
| Suburban living is all about being safe from
| criminal hordes outside the gates - whether real
| or imagined.
Sure, you will always get bigger spaces for the same price - that's why they're called suburbs, but the marginal utility of space decreases pretty rapidly. There are many cities where owning a sufficiently large space is indeed affordable. In fact this describes most cities outside of SF and NYC where we're packed like sardines.
People stopped living in cities because drug and crime became rampant, and quality of life dropped precipitously. That was the instigator, and still a cultural cornerstone of the suburban lifestyle, despite the revitalization of urban America.
People were fine living in apartments rather than owning a whole building to themselves - until the environment went to shit. They had the ability to get big houses outside the city for decades but didn't take the option until their urban neighborhoods collapsed. I suspect they still are fine with not owning a large house.
And we do see this in some places, where buying a medium-sized flat in a nice neighborhood close to good schools is as desirable as a big house with a big lawn in a nice area.
If you look at suburban developments all around the country, you'll also notice an explosion of smaller houses and townhouses - places that are in many cases no larger than apartments in the city, just in upright standing form. Space is a detail to most of the population, not a core factor.
For example, in Toronto the real estate prices are sky high in the city (e.g. I've heard of just a single floor of some of those large houses in The Annex going for upwards of $800k). There are a lot of condos being built (and already built), but they are all aimed at single people or childless couples, not necessarily at families. Two or three bedroom condos are few and far between, meaning that they aren't exactly cheap.
Take a look where the most expensive houses in Hamilton or St. Catharines or Kitchener are and where the "bad" parts of town are.
Cost is also tied up with the issue of public versus private schools, and it's that issue more than any other that in my experience is the reason urbanites become suburbanites. Then generalized negative perceptions of American cities (as cesspools of crime, noise, high taxes, etc.) keep many suburbanites away.
Those perceptions are half-truths at best, but a perhaps even bigger problem is that for the great many people who haven't lived it, there's no consideration of the benefits of an urban lifestyle. Of course you're going to choose to live in the 'burbs if you only see the city's detriments and not also its commensurately higher (or better) advantages.
0. In cities like San Francisco, a lot of that cost is due to land-use regulation. But in a typical mid-sized Midwestern city like Cincinnati or Kansas City, where public transit is poor and parking is provided pretty much everywhere, only the true urban warriors try to get by without a car. So parking is a big driver of the cost of city living. Structured parking costs $40,000 or more per space, and median home prices are well under $200,000. Ten to twenty percent or more of the cost of a condo downtown is parking, and you still have to pay for a car. (And it should go without saying that the benefits of city living are greatly reduced if you need to drive a lot anyway.)
The sorry state of American cities is due in huge part to state distortion. The social services for the poor are heavily concentrated in the cities, so that's where they go (has the irony ever occurred to anyone that people complain about not being able to afford SF, NYC, etc, but at the same time those places are filled with poor people living in project housing?). Social services for middle class people (roads, good schools, etc) are concentrated in the suburbs, so that's where they go. Then the municipalities prevent all development, causing skyrocketing rents for people who want to try and live in the city anyway. City and state governments try as hard as they can to get people to leave their cities.
I can't find it now, but I know Megan McArdle has written about how there is a bathtub-shaped curve (my word) for income distribution in many parts of NYC. You can be poor, and you will do okay. You can be really rich, and you will go well. But in the middle it becomes a desert.
Also self driving cars wouldn't need as much distance between cars to be able to stop safely so you could physically fit more cars on a given stretch of road.
Automated cars have the potential to reduce the lag in speedup after breaking, eliminate most accidents, and pick better routes, and all while letting you do other things with your time. Commute time is a huge reason to do this.