[jseliger]

That's assuming there are no technological improvements in transportation in the long, long term. Which is, honestly, in this time and age, ridiculous.

I understand what you're saying and you might be right. But you could just as easily have said the same thing in the 1960s ("we'll have flying cars"), and yet here we are in 2014 and the places that built and maintained mass-transit systems are on average doing better than those that haven't (Richard Florida discusses this in a couple of books; so does Edward Glaeser in The Triumph of the City.)

[ekianjo]

The countries which invested in train in the 1960s are not really doing very well as far as I can tell. Japan and France are both in recession or stagnant, and it's not like trains has replaced other means of transportations. If anything, plane carriers have become cheaper than trains now, and there's also competition from the road (bus lines). So I'm not sure, country wise, that investing in high speed trains has been very profitable for the countries involved.