Years ago I thought the idea of regional high speed rail lines in the US was a great idea, but I think the time for that has come and gone.  The future seems to be clearly moving towards autonomous cars (and buses one presumes).  Why sink billions into high speed rail when on our current pace it will be only a couple decades before we have all electric cars powered by solar and other clean energy sources that are 90 something percent autonomous?  I think most people would easily choose a 5 hr autonomous car ride from LA to SF with complete freedom of movement in both cities compared to a 2 hr train ride with possibly a couple hours in both cities dealing with connections getting you to your specific destinations.