[ajmurmann]

The problem, as always, isn't size but density. Outside the east coast there is very little density. It's almost unfathomable having grown up in Europe how big and empty even large areas at the west coast are. This gets especially obvious when you get away from the central freeway that goes up the coast. Where I've visited our lived in Europe or Asia these areas would still be largely inhabited and have smaller towns sprinkled all over with small, frequently even walkable or bookkeeper distances between them. At the west coast, away from the freeway there is often nothing for miles and miles and then when you hit a small town is often partially abandoned. In other parts of the world these surrounding areas would provide passengers to the central transportation arteries via slow train and you'd have viable, slow trains transporting passengers to the major stops along the high speed track. None of that would be viable here. When the LA-SF highspeed train was planned they added stops in podunk towns to make it viable, IMO they were also removing any speed that would be comparable to airplane for any interesting connection.

And that's the west coast, once you go inland you'd maybe have one viable stop in most states of you want to keep it high-speed.

[dontlaugh]

There are very sparse areas of China too, yet there are high speed trains between major cities across regions. Then there are additional slower lines with more stops from major cities to other nearby localities.

US coast-to-coast trains wouldn't need stops to be viable. They'd just need to initially be subsidised significantly, much like the current fossil-dominated industries are.

[ajmurmann]

FYI: The Nozomi Shinkansen would take 13+ hours from NYC to LA at max speed if it was going on a straight line the entire time and completely ignore any constraints like mountains, etc. Even in this ideal scenario and it being subsidized to cost the same as an airplane ticket why would anyone choose the train?