I am a fan of train projects when those projects start with a problem that might be solved by a train, and then work forward to the train. The problem is that in America, those routes are difficult to build, because they're places where there's already a lot of stuff. Rights of way are expensive and time-consuming to obtain, and the project is bound to be blocked by well-organized NIMBYs.
And so the idea seems to have become to build trains where it's possible to build trains, and hope that development follows. But trains succeed where they are better than some alternative form of transportation. In the case of Tampa to Orlando, they're worse than a car, and there isn't even any air travel to replace; in the case of Fresno-to-Bakersfield, it may be better than a car for a few passengers, but there are too few passengers to make the trains better than cars for the environment.
Meanwhile, projects that do make economic sense, like an actual high-speed Acela, or Southeastern High-Speed Rail Corridor, are going nowhere. They might have a better chance of success if rail advocates hadn't abandoned them in favor of building whizzy demonstration projects with dubious economic appeal.
Sound thoughts via Megan McArdle here, for sure. The Acela, which goes right behind my house, could travel the 222 miles from Boston to NY with a handful of stops in, what, 90 minutes at 150 mph? Or in 2 hours at 120 mph. So, make that happen? Oh, no! Keep it slow, take 4 hours or more, and charge almost as much as a plane ticket. Spend money, accomplish almost nothing.
See, this gets right at Obama's alleged goal of investing in ideas that will really make us better and keep us ahead. Let's get rid of "if we build it they will come" and replace it with"if we really need it we should build it." File this under not brain surgery.