The area surrounding the Rhine Valley is the most densely populated part of Europe. I recently drove up the west coast from SF and at least from I5 it seemed li

The area surrounding the Rhine Valley is the most densely populated part of Europe. I recently drove up the west coast from SF and at least from I5 it seemed like Eugene-Vancouver Canada was pretty built up most of the way. It’s a bit more sparse on the 100 mile stretch between Vancouver WA and Olympia but it’s not really that far, two thirds of Hamburg-Berlin which is less densely populated than western parts of Germany. But just look at France or Spain to see high speed rail working well in more sparsely populated countries. I think the bigger problem is how much you need a car within American cities which tend to be much more spread out than their European equivalents, though Seattle, Portland and Vancouver Canada aren’t terrible in that respect. It probably makes sense to prioritise regional rail before HSR, but then if you have to build new railways to get separation from freight traffic, electrify and remove crossings so you can run 100 mph European regional rail speeds and frequencies I guess you may as well build HSR.