Trains in the US carry freight, not passengers
Total carloads on U.S. railroads in March 2017 were up 7.3% (87,183 carloads) over March 2016; excluding coal, carloads in March were up 2.7% (23,337 carloads). Intermodal containers and trailers were up 3.8% (47,180 units) for the month. Year-to-date total carloads through March were up 5.7% (180,665 carloads), while year-to-date intermodal volume was up 1.4% (47,977 units) over last year.
That's about "carloads" of freight, not passengers. After the advent of the automobile and air travel, passenger rail was no longer profitable 50 years ago. That's why we now have a federally subsidized Amtrak system.
It's also why Warren Buffett invested in freight rail, not passenger rail.
I don't share his libertarian philosophy, but Randal O'Toole is good on the train delusion. See O'Toole on Trump and infrastructure.