Just the high-speed trains here carry just under 3 billion passengers per year. Divide it by respective populations (land area is roughly equivalent) and you've got the equivalent of the USA carrying 735 million passengers annually.
And that's just high-speed trains.
If you factor in regular rail we can add about 730 million extra passengers (183 million extra passengers for US population adjustment).
The USA has a whole lot of work to do before it catches up even on regular rail, not to mention high-speed.