The Auto & oil industry has been a powerful lobby for keeping the car as a top personal transport method in the US.
My guess a high speed train in California is probaby not the best idea, anytime there is a moderate earthquake the high speed line would be shut down till the rail had been checked. High speed trains on the lines would probably have to stop and the passengers would have to get off the train and be put on a bus or the train would have to slowly complete its journey.
With planes - the runways and taxiways need to be checked after an earthquake - only 2 or so miles.
The maintenance of the high speed rail lines is a big expense.
http://www.lowtechmagazine.com/2013/...y-network.html
http://en.wikipedia.org/wiki/High-sp..._United_States

If Tesla Energy is successful or has more plans rather than the 'train tube' idea that was previously released, A Tesla battery/ renewable energy powered moderate speed type train could be a future idea. Train pulls into station - robot arm with a stack of battery packs on nut runners change battery packs, no need to have all the electricity overhead lines with all the maintenance costs. A train version of the tesla car, steel wheels on steel tracks has less friction than rubber on tar = efficiency.