It's still likely a waste. By the time it is at the point of highest use, or proposed highest use, when the most money has been spent, and returns on investment should be coming in... cars will be capable of driving themselves, with passengers working in their back seat while they commute, with good, satellite based mesh wireless internet.
A driver less car absolutely can. But there is an inflection point where cost of daily tickets two ways, plus cost of driver less cars two ways, each day, every day, becomes more expensive than having the car independently, and/or ride sharing the vehicle, which is ultimately the true goal of driver less.
Why not? I don't see them as necessary, but that doesn't mean it isn't possible. We have humans driving 200 mph, in close formation, now. Yea, I think the automation can handle it.
I'm just pointing out that high speed rail is an alternative to domestic flight, and is not necessarily a competitor for driverless cars/personal vehicles. They can coexist.
Driverless vehicles are not a panacea. If everyone owns personal ones, traffic may actually increase due to avoiding parking, for example. And even with driverless, a road network will have a capacity to where things start getting gummed up, the same as a pipe has a volume and pressure capacity.
Let me paint a picture for you. You have a car, that can drive itself anywhere. And while you're at work, you're like... wow, this thing could be Uber'ing people, and making me money, while I don't need it. So you schedule it up as a driverless Uber'ing machine. How long before everyone else realizes they can also do that... and then how long before everyone realizes that they don't actually need their own car... and then how long before everyone realizes that nobody needs their own cars, and they become just public? And then how many of those cars could be bought, right now, for the price of a single high speed rail that only serves California? And requires humans?
Don't think I could fully trust it. Seems I recall a fiery wreck of a Tesla with 3 passengers and none in drivers seat
You are manufacturing a conflict that doesn't exist. Imagine you are in southern California and want to go to northern California. And there's a train that gets you there really fast. And you can use driverless cars to get to and from the station.