Public transportation is typically worse than using a private car. You can't decide when to leave, you pretty much need to plan your trips around public transportation. They don't take you directly from A to B etc.
This is typically true in North America, but it is not a fundamental law. Particularly, in Europe, but also for some trips in Sydney, Vancouver, et cetera, I have found public transit superior to a private car. The key is to have as wide of a network as possible, frequent service (every 5 minutes so you don't need to think about schedules) and a average speed that is higher than the car (doable with trains, dedicated bus lanes and so on). Anywhere that there is enough traffic to cause congestion ought to be a viable place for public transportation . . . population density is not necessarily the driving factor. In fact, in some situations, a high population density might allow people to move less as they are closer to shops, work, friends, et cetera, rendering transit less important.
No, the problem with public transit in North America isn't some fundamental flaw with public transit, it is because we tend to half-ass it.
Population density is key to mass transit otherwise you have to spend a lot more money to provide frequent and convenient service. You can't get around the need for high enough ridership to make a transit system financially viable. Sparse population density = higher per rider cost = more difficult to offer frequent service without losing a lot of money.
In North America part of the reason we don't have as much mass transit as other parts of the world is because we like our urban sprawl and that makes it difficult to make the economics work out.
I don't know about other parts of Europe, but where I'm from public transit is most definitely not financially viable. Even in the big cities, it produces millions of euro of losses each year. Those are covered by taxes.
The problem in North America isn't [just] the suburban sprawl, it's also that you want to make a profit off of everything. Sometimes some things just need to be a public service because it's better that way.
Roads are (mostly) not free, and also cost millions of (insert currency unit here) which are covered by taxes. In particular, the asphalted road in a residential street occupied without charge by someone's expensive vehicle is being paid for by, among other people, me -- and as a non-car-owner, I gain essentially no benefit from the provision of this parking space. So clearly, we've opted as a society for subsidizing public services -- but only certain services.
I think the difference is in the perception that roads are static and once built just sort of stay there for everyone, whereas public transit has a lot of running costs. Sure roads have a lot of upkeep cost as well, but it's not as obvious.
Then again, the roads I've seen in the US are so shitty I'm [almost] certain there's no upkeep being done anyway.
The way this works in municipalities or low-population regions of states (which is what most people experience traveling through 95% of the United States' road miles) is that roads are left to deteriorate until such time as they can't avoid fixing, and preferentially might be completely rebuilt which takes a different flavor of money that can be subsidized by the federal govt.
Regions with affluent populations and dense metros essentially have their own road budgets and taxes to keep conditions acceptable.
The other problem in the states is that the weather varies very strongly; this coupled with snowplows and road freight does a number on roads in short order. Some stretches have to be resurfaced yearly. Doing this is expensive and disruptive, so sometimes it is only done in the worst spots if the other parts can wait.
Roads have to be maintained, the cost is non-trivial.
The roads in the US are absolutely a dream compared to say Indonesia, or even China where new roads tend to crumble after a few years of iffy maintenance.
I can think of a few benefits you get from your neighbor's parking space, but the most important is the increased economic output of your neighbor due to their happiness with suburban life.
The challenge for mass transit systems in the United States is that if the operating costs are so high that it requires heavy subsidization from taxes it becomes a very tough sell politically. "Our taxes are being raised by how much to subsidize the subway???"
Perhaps that's just a failing of how mass transit systems are sold to the public though. If your mass transit system takes several hundred thousand people off the road every day and significantly reduces gridlock it makes everyone's commute better and wastes a lot less time and gas. Maybe that's how these systems need to be sold rather than, "It'll run profitably after X years."
They also promote economic activity (people can get to work and spend less time commuting). Even cities in red states are striving for more of that (though to be fare, even those cities are mostly blue).
Mass transit in the USA used to be mostly operated by private companies, and yes they made a profit.
I don't think anyone really expects government-run mass transit to be profitable, I for one would be happy if it were less of an enormous money pit. Given the level of corruption in most public transit authorities however, I don't hold out much hope.
The private companies couldn't compete with public subsidized roads that came online in the 20th century. If you want to see transit companies making a profit, try highly dense Japan, and you'll still pay more for it.
As if the USA was a third-world country with a high level of corruption compared to say...China, which many conservatives/libertarians "praise" for its cost and efficiency.
This is typically true in North America, but it is not a fundamental law. Particularly, in Europe, but also for some trips in Sydney, Vancouver, et cetera, I have found public transit superior to a private car. The key is to have as wide of a network as possible, frequent service (every 5 minutes so you don't need to think about schedules) and a average speed that is higher than the car (doable with trains, dedicated bus lanes and so on). Anywhere that there is enough traffic to cause congestion ought to be a viable place for public transportation . . . population density is not necessarily the driving factor. In fact, in some situations, a high population density might allow people to move less as they are closer to shops, work, friends, et cetera, rendering transit less important.
No, the problem with public transit in North America isn't some fundamental flaw with public transit, it is because we tend to half-ass it.