Building it helps stimulate demand for more non-car centric infrastructure. My city built a light rail years ago, and despite stopping at pretty much a single line, tons of development popped up at most of the stops and a lot of housing along the line. None of that would have happened in a car-free way without the rail coming first.

The US desperately needs a highspeed rail network to rival the interstate highway network. But of course, that can't happen, America is too big for railroads, apparently.