Megan McArdle has a post asking why we don’t really have much fast rail in the US. There are some good posts in the comments, but I would like to take a crack at it.
In Germany, a normal ICE train generally goes about 100 MPH most of the time, dropping speed when it gets near cities, and a bit faster in fields. ICEs have an expected speed of about 120 MPH for standard operation, so that’s about what you could expect an American train to do. Also, German rail is heavily prioritized toward passenger travel, with freight a distant second. In the US, meanwhile, we ship a larger percentage of goods via freight than Germany (which mainly uses trucks in-country). Thus, German trains have to run on a relatively tight schedule, as people must make expectations that the train will be there at a particular time and will get to their destination at another particular time. But in the US, trains do not have to run on such a tight schedule—what’s the difference if wheat or automobiles or coal gets to its destination a few hours or a couple days later? Because of this, American trains do not run as regularly, but do run at higher car capacity, and that’s the logistical trade-off you have to make.
If you want high-speed rail across the US, then, you can either rejigger the entire system or set up a second rail system. Given the general characteristics of the US (huge, generally flat, generally empty spaces with low-density housing), rail-based freight is quite advantageous for cross-country, interregional, and extended intraregional travel, meaning that you would not want to dismantle a functional system. Thus, it would be better to build a new line, if such a thing is feasible.
The next step to consider is density. Again, countries like Germany and Switzerland are very popular in these kinds of discussions, but there’s something important to think about: Germany has 80 million people in an area roughly the size of Ohio, Indiana, and Illinois. In comparison, the three states I mentioned have about 30 million between them, and includes the #5 and #7 states in terms of population (as of 2003). The Chicago metropolitan area alone is responsible for over 9 million, and Chicago itself has a population of 3 million. This means that a third of the region already lives in the Chicago area and would not have that much use for a lot of fast rail, and they already have some amount of metro rail. The upshot of this is that it could be difficult to have a decent set of rail lines. You could probably run a 3C rail line from Cleveland-Columbus-Cincinnati, link these off to Indianapolis through Dayton, and then run to Chicago and Urbana-Champaign (like Amtrak already does), maybe throwing Toledo and Gary in a second line going through Cleveland. Whether this would actually be profitable or not is another story, but these are the only lines that I could really think of, as I’m having trouble coming up with many other potentially profitable opportunities. In Germany or Switzerland, meanwhile, you have a lot of people living in a relatively small area, so there is a much larger population base for rail travel.
Third, we have to think about distance. Very few people are going to take a train from New York to LA, given that it would take at least two days to run. Instead, you’ll just fly there and take a few hours. On the other hand, inter-city travel within a region is a possibility. As I noted, an Ohio-based rail line would probably touch 5 Ohio cities and link to Chicago, Indianapolis, Pittsburgh, and Louisville (as well as that state up north, I suppose), but I wouldn’t see many people going by train much further than that. Once you start talking about Philadelphia, Milwaukee, St. Louis, Atlanta, or maybe even Chicago (it would be kind of on the edge), it starts making more sense just to fly. After all, it’s a one-hour flight from Columbus to Chicago and a similar flight to Philadelphia. At the same time, it would be about a five-hour drive to Philly and 6 hours to Chicago (depending on how far into town you want to go), so estimate 4 hours by train to Philadelphia and about 5 to Chicago. In Germany, it takes about 5 hours to go from Freiburg to Berlin via ICE, and at this point, it starts making sense to take a train down to Basel and fly to Berlin (and it usually turns out to be cheaper that way). So this would appear to be the limit as far as how long the average person could stand riding in a train, given the option of air travel. This means that we would not have cross-continent fast rail, and there are big swaths of the midwest and southwest that would not be profitable at all, given the extremely low density of most of the US.
Our next step is to figure out how to build the lines. It would make sense in the non-eastern-seaboard areas basically to follow the highway and build around that way. For example, Cleveland-Columbus-Cincinnati and Pittsburgh-Columbus-Dayton-Indianapolis would be relatively easy to set up, given that there is a lot of flat land and highways already there. Going through the cities would be more difficult, though, and would be rather costly. Then, on the eastern seaboard, you have to deal with the Boston-NYC-Philadelphia-Washington-Norfolk mess. Yeah, that’s probably a profitable line, but McArdle points out that the existing track is twisty-bendy. This doesn’t even mention the difficulty in getting the land to build straight rail through the region, where land is much more expensive and more-developed. It is possible, but would involve a lot of land purchases.
Finally, you have the issue of location and time saved. In Columbus, for example, I could see a train station somewhere near the airport and basically looping around the town to avoid cutting through swaths of existing buildings and roads. The upside to this is that it would be feasible and not extremely expensive, but the downside is that such a plan would cut down on the likelihood of travel. For example, I live slightly southwest of Columbus, meaning that I have a good head start on the way to Cincinnati or Dayton. Even though a train can go faster than I, once you factor in the 30+ minute drive, time spent parking, time spent waiting, time spent getting the train going to full speed, etc., I could beat it to those cities. Going to Cleveland, Pittsburgh, Detroit, Toledo, Indianapolis, or Chicago is a different story, and Louisville would probably be a wash (given that such a train would stop in Cincinnati), but if I’m going to fly to Chicago anyhow (which I personally would), it basically means that there are three or maybe four routes that I would ever ride, and given the low density of most American cities, this holds for a lot of people.
All in all, I could imagine a few profitable routes, but even my Midwestern Express would have difficulty getting off the ground, I think. Fast rail is an interesting idea and, if it is cheap enough, could be a nice mode of travel for college students who go to a regional school (like I did, going to Dayton), but rail is not a particularly cheap mode of travel—even when you receive major subsidies, like German rail companies do—is not particularly fast, and would have difficulty serving a lot of people efficiently. To make one final comparison to the German setup, pretty much every German who lives in a town (no matter how small) will have access to a rail station and a train at least once every two hours. A fair amount of traffic from Berlin to Frankfurt actually comes from people who live in neither city, but rather in a smaller city in the region and who are serviced by slower, local trains. These trains almost always run at a loss and would not exist in an American setup. This means that any potential rail setup in the US would involve driving to a fairly major city’s rail station. Even if you suppose that each city could have two or three stations, somebody who lives in a smaller town would have to drive a fairly long way just to get to a train station, so my hunch is that intercity rail probably would not work, given that the US is built around highway travel.