The distance from Los Angeles to New York is 2800 miles — which makes high-speed rail impossible in the USA. At least, that is what Megan McArdle argues in the Atlantic:
Yesterday, we rode the high speed rail from Hangzhou to Shanghai. It took 45 minutes to go about 110 miles, and the ride was smoother than any US form of transportation…Unfortunately, I don’t think we’re going to get it. To see why, compare the map of the 10 biggest cities in China:
And here is the map Megan proudly presents of China’s largest cities:

And here is the map Megan proudly presents of America’s largest cities:

The crux of her argument is that America’s 10 largest cities are more spread out than China’s 10 largest cities. Why is high-speed rail limited to only the 10 largest cities…who knows?
For comparison, here is a map of Europe’s 10 largest cities. I hear Europe has a network of high-speed trains too.
Those points in the upper northeast are Moscow and St. Petersburg. Over in the far southwest corner is Madrid. Distance from Madrid to Moscow is roughly 2500 miles. (No fair throwing Istanbul you say? Well, Turkey is building high-speed rail network too.)
Not sure which data source you’re using, but I think by any metric (city limits, metropolitan, urban area) Berlin has a higher population than Frankfurt…
This is a post on the same subject that made on the Planetizen blog awhile ago:
I am getting tired of hearing that North America cannot support high-speed rail (HSR) because we lack the densities of Europe. Yes, France is much more dense than the US or Canada, but that is not what drives HSR. Take Paris-Lyon for example – much denser population between the two cities than what is typically found in North America, but note that the TGV serves those two cities and very few points in between. The overall density doesn’t matter, but the large cities at either end do!
In North America (outside of the very densely populated US northeast corridor) there are many examples of city pairs like Paris-Lyons that would work perfectly. Take the following examples:
• Chicago-St. Louis with a stops in Bloomington (or Champaign) and Springfield
• Chicago-Minneapolis with a stop in Madison
• Chicago-Philadelphia with stops in South Bend, Cleveland, Pittsburgh and Harrisburg
• New Orleans-Memphis-St. Louis
• Houston-New Orleans-Atlanta
• Windsor-Hamilton-Toronto-Montreal-Quebec City
• Edmonton-Calgary via Red Deer
• Vancouver, BC-Seattle-Portland
All of these mimic the links between highly populated nodes that are served by HSR in Europe. Sure, there’s never going to be HSR from Toronto to Vancouver or Chicago to LA, but large city pairs that are spaced 400-800 km apart with one medium city between them are perfect opportunities for HSR. In that respect, the climate for HSR in North America is no different than in Europe. The potential market exists, and the geography is definitely workable.