The Sentinel ICBM project (already at 2x initial budget, and set to balloon further) will be the most expensive project since the interstate freeway system was built.

https://arstechnica.com/space/2026/02/the-air-forces-new-icb...

So, an all-city high-speed rail network would certainly be achievable for a small fraction of the total US military budget.

well yeah. the pentagon wastes 1 trilly per year. a lot of stuff can be paid for with that kind of money.