You really can't compare Europe to the US. They are tiny. For example, one of the largest countries in Europe is France: slightly less than the size of Texas. It's metropolitan population is 65m. Texas is only 28m. Other countries there are even more lopsided. Just as with cellphone networks, smaller area is easier.
That's not actually true. The US is 3,794,101 sq mi. Europe is 3,930,520 sq miles
However, Europe is almost entirely concentrated in walkable, urban areas -- even beyond the major cities, small towns are accessible by train, navigable by foot, and have excellent support in the form of public transportation. If people do have "cars," they tend to be tiny or Vespas.
There's no reason we can't have the same system here, except that we absolutely suck at infrastructure investment. It's really not that hard to build an urban environment, and it's overwhelmingly popular with people who can afford it. The exurbs of Las Vegas and Miami are completely worthless, and will be even more so in a future with higher fuel costs, water scarcity, and resettlement in urban environments.
I'm sorry, but that's not how urban design works. We're not forced to develop proportionate to land mass. Your argument is seriously that the existence of the Dakotas prevents us from building decent cities? Are there so many people in Wyoming that we just don't have the population to build decent subways in Seattle?
We're trapped by a car-centric lifestyle, and it's absolutely poisonous.
Yes, basically. Though it more like the existence of twice as many twice as small cities. It also means that we devote huge amounts of infrastructure dollars to the middle of nowhere serving virtually no one. Look at the subsidies we give to "rural phone companies" or the postal service.
