The Infrastructurist has highly useful and informative links about high speed rail in the US.
Yes, HSR will be expensive. But when completed, it would revolutionize transportation. Imagine being able to go from, say, S.F. to L.A. in couple of hours, leaving and arriving at downtown locations, not at an airport.
There’s a teensy little bit of noise being made about high speed rail lines in Alabama, especially here in Huntsville, where that argument expands into a very big campaign to get more public transportation period. It’s bad because its conservative Alabama, but its good because Huntsville is like straight up owned by construction and real estate tycoons, and they’re not really shy about splurging on crazy infrastructure.