Traveling by air in the United States is a pain these days.

Planes are crowded, ticket prices are rising and the airlines are adding fees at a dizzying pace.

And if you’re traveling to a major city, chances are good that the airport is far enough away from the city center that you’ll have an expensive and time-consuming taxi ride into town.

It all begs the question that so many have asked: why did the country let its rail system wither to the point of extinction?

We could argue that for awhile. But most experts agree that Americans’ love for their automobiles spelled the end of a workable train system in this country.

Sure, there are a few places still linked by rail. You can catch trains from New York to Washington, and between a few other cities, and downtown terminals eliminate the need to go 30 miles to an airport. But by and large, a healthy train system is nothing more than a memory in the United States.

 (We won’t even get into Amtrak.)

Europe still has a viable rail system that links virtually every city on the continent. Because European countries have such high gas taxes -- you can expect to pay 8 to 10 bucks a gallon for fuel -- trains are a cost-efficient way to travel.

And now, many European cities are clamping down on cars more than ever before, passing all sorts of regulations intended to get people out of their automobiles and onto their feet -- or their bicycles, or scooters, or however else they want to travel other than by auto.

A recent news story chronicled the efforts of such places as Zurich, Paris, London and Stockholm to shut down traffic and encourage pedestrian walkways. A few American cities have adopted similar measure but to a far less extent, comprising only a block or two.

As one transportation guru noted in a news story, American cities have adopted a philosophy of adapting cities to accommodate traffic, while Europeans are trying to stymie traffic.

Urban planners on the continent don’t pull punches; they acknowledge they’re going to punish drivers who insist on motoring in downtown areas, either by punitive fees or by making the urban driving experience so unpleasant that few will choose to head into a city in their cars.

Zurich, for instance, has placed severe speed limits on downtown traffic and has removed crossing signs entirely in many areas, allowing anyone on foot to cross wherever they wish and forcing cars to stop for them. Traffic lights have been erected at close intervals.

Those measures have slowed traffic to a snail’s pace, leaving drivers muttering that the next day, they’ll leave their cars at home.

One official there said the city’s goal is to re-conquer the downtown for pedestrians and eliminate cars.

London and Stockholm have taken a financial approach, levying heavy fees on any motorist who enters the center city.

Of course, European cities were established centuries before American ones were, often with narrow, winding streets that don’t suit themselves to cars. So there’s more incentive for them to go back to the age-old practice of walking.

The measures are working. Many residents are selling their cars, instead walking, riding bicycles and using public transport, and then employing a car-sharing service for out-of-town trips.

Such concepts would be viewed as radical in the United States but would certainly help move cities toward less traffic congestion, healthier pollution levels and a more pleasant experience for pedestrians.

Whether we’ll buy that -- or even consider it -- remains to be seen. We’re a nation of drivers, and perhaps the only people who love American cars more than those of us who own them are the billionaire sheiks of Mideast oil-producing nations.