Earlier quoted context omitted.
I didn't say anything about roads, but it's not true that roads are unprofitable. Roads are paid for by fuel taxes and vehicle registration fees. California's gas taxes raise $8 billion per year. The state's registration and licensing fees collect another $12 billion per year. The state spends $18 billion per year on Caltrans, meaning that vehicles provide $2 billion in revenue for other state programs. BART takes 30…
You might consider the climate and carbon impact of those flights vs rail. Many of the rail lines are subsidized in countries with extensive rail travel. So they don’t have to be economically viable, it’s viewed as a public good, contributing to general economic development.
I'm not saying that countries with lots of rail are wrong. I'm saying that passenger high speed rail doesn't make sense in the US (at least, not outside of the northeast). We're too spread out.