I know it would be attacked politically, but I wish in the US we would be more open to hiring foreign firms for these kinds of projects. Could we have high-speed rail if we just asked some French or Japanese company to build it for us? And we should structure contracts with them in a way that keeps the plans from being changed for political reasons. "Sorry state senator, we can't alter the route to pass through that town without re-opening negotiations which might cost billions."
I think the lesson here might be to solve your problems on a more local scale, as the fit of the solution is as important as checking the boxes.
What works in Japan works in Japan because it was a solution built for the problems, politics, and people of Japan. Sometimes there are lessons we can take from projects in other countries, other times it turns out like Cali HSR where the proposed 'foreign' solution might be logical but not politically tenable.
The problem isn't physically building the rail, the problem is the legal framework in which governments operate in. Multiple rounds of environmental impact statements, eminent domain lawsuits, preferred contractor RFP's, zoning, permitting, endless red tape...
