>A west coast HSR network is just obviously practical! Beijing-Shanghai HSR is 1300km; SF to Seattle would be the same. It'd be 4-5h on a train. Right now it's 2.5 hours on a plane plus a recommended 1.5 hours for security and boarding plus transfers on each side--I'd rather take a high speed train If I could! SF to LA could be ~3h. 90 minutes on a plane plus lead time and transfer times and it's competitive. Again.

So just to be clear you are saying at best the time difference between flight and HSR would be minimal - so where is the payoff for the billions the infrastructure would take to build. If it's purely capacity couldn't you spend a fraction of the billions you'd spend on the new infrastructure to bolster the existing system?