To be fair, part of the inordinate expense is just because it takes longer for the environmental reviews (costs are in expected year of construction, so pushing a project a decade into the future can increase costs by 30-40+% (inflation + interest) depending on the specifics, even if everything else costs the same).
That's why the cost estimates for CA HSR jump a bunch every time an administration hostile to it enters the white house.
> project a decade into the future can increase costs
A very good point.
I don't agree we can blame Trump for HSR though. 2/3 of the time that has passed have had Democrats in the white house. HSR is nearly all pure-California-style self-inflicted wound. And honestly it's just the most visible project California has failed with, there are many others. The one I'm personally angry about is Prop 1. We're now 12 years after, and have no additional water resources even broken ground. It's shameful.