Comment by zdragnar
> but of course, this being the US, it's not really a viable means of transportation.
Surely if the problem with roads and cars is that private transportation takes up too much room, then widespread private train cars by everyone would be equally problematic pretty much anywhere in the world.
Long distance routes do not take up that much room - most people don't do it often enough. You wouldn't want this for getting to work every day - that wouldn't work. Though a train car can safely follow closer than a auto so it would still be better than private autos.