HSR only makes economic sense in the northeast. Everywhere else is too spread out for rail to compete with air travel. The most popular air route in the western US (SF-LA) isn’t worth making high speed rail between. The project is expected to cost over $30 billion. Assuming 100% of air passengers use rail (4 million per year), at $150 per ticket it would take 50 years to break even… and that assumes zero maintenance costs. Also it would be slower than taking a plane.