I believe you're right that the US northeast is denser than many European countries, but the rail definitely isn't as good. The only "high-speed" rail line is

I believe you're right that the US northeast is denser than many European countries, but the rail definitely isn't as good. The only "high-speed" rail line is the Acela, which is slow and expensive. Other rail options are even slower, not all that cheap either, and not very reliable. Compared to the rest of the US, northeast transit is better, but that's a pretty low bar.