Wait, the US finally comes up with some new cool mass-transit technology and we're not even building it here?
Shame.
Shame.
See: BART
What this resulted in was - a wider track gauge than any other used in the US - bespoke rolling stock with different braking, control, coupling systems - untested ATO that had several early failures
The first two have had lasting impacts; servicing BART equipment is very difficult because no one else has ever made traincars like that, and it makes it difficult to extend BART over existing rail tracks. The expensive of all this "cool" factor is at least a factor of two over standard rail projects, which is why eBART was built as a normal diesel rail line instead of as a BART extension.
Other examples of "cool" transit technologies that ended up aging poorly because of their rarity are monorails and maglevs. With economies of scale it's hard to beat trains, and trains already go to 220+ MPH; there are very few markets where you would need to go significantly faster via land, and where doing so would be a big advantage over air travel, as Hyperloop is proposing.
China has 16,000 miles of high-speed rail. We have essentially zero. It makes more sense to build this in China.
They already have high-speed and low-speed maglev trains.
Not unless you nix the tube and just build a reliable high speed rail system.
I know it feels that way, but it's not strictly true. Here in Seattle in the last decade we've built a new floating bridge, multiple miles of underground light rail track, and nearly two miles of deep bore road tunnel.
I think there is a real problem that our new infrastructure is way too expensive and takes way too long to build, but we've demonstrated that we can definitely build new stuff.
They could've used that to link up Seattle, Tacoma, Redmond, Kent, Bainbridge Island, Vashon Island, and the entire Seattle area.
And to keep costs of building the infrastructure down, then they should consider outsourcing it, and hiring Chinese labor. (Apparently, the Chinese are very good at building railroads.) That way, you keep development costs down, and afterwards, the local citizens can enjoy first-world infrastructure, at low rates.
But, when infrastructure projects become billion dollar estimates, then that just kills any opportunity of it ever being developed. Simply, because it now becomes a major high-paying jobs program.
Oh, its in an expensive pointless vacuum tube? Is that the "new/cool" part?
Edit: clarified what "it" is.
Edit: Ah, your stealth edit indicates you thought I was talking about Hyperloop! I wasn't. I edited the top to indicate that.