This is completely irrelevant to the point I was making: arguments about how America "isn't dense enough" for rail is ignoring the fact that America actually is

This is completely irrelevant to the point I was making: arguments about how America "isn't dense enough" for rail is ignoring the fact that America actually is quite dense ... where Americans actually live. Our tenth densest state is denser than a country famous for its usage of high speed rail for passenger transit. Any difference in infrastructure is down to political choices, not density.