We all know being able to get from A to B quickly is nice, but I think it is underappreciated how much fast trains are like little wormhole ships. What if you could step on a train in NYC and be in Boston in an hour, with relatively inexpensive service every 5 minutes? Suddenly, NYC and Boston are effectively "next to" each other.
This train will have a trip time from Tokyo to Osaka of 67 minutes. That's half the current (already fast) time.
At some still unfixed point in the future when the magnetically levitating Linear Chuo Shinkansen train makes its first 505km per hour journey across central Japan, it will streak through Shizuoka prefecture in a little under 64 seconds.
It has taken more than a decade of wrangling for Japan to be able to say that with confidence; it will be many more years before anyone is actually boarding the train itself and likely many more years after that before people genuinely think of central Japan as the “linear economic zone” imagined by the government that is seamlessly joined by the train.
A couple of years ago, I was somewhat "amused" to learn that this project was being held up by one obstinate governor, the governor of the 64 second Shizuoka prefecture. That's the kind of problem I generally imagine is unique to the US's fractured governance and legal system.
As for how we would pay for it, well, look up the cost of your local highway interchange upgrade project.