The longest trip between the major cities on the Chinese map is just slightly longer than the DC-Chicago trip would be. It’s no coincidence that the only place we have anything that could even be arguably dubbed HSR is the one area where four cities are pretty tightly clustered together. And that doesn’t go very fast because it uses existing rights of way, and because the politicians that fund it like to have it make stops in their city. (Q: Why does the Acela stop in Wilmington, Delaware, which is a quick drive from Philadelphia? A: Because Joe Biden likes to ride it.) Stops are the enemy of speed.
Moreover, the Chinese government does not have to worry unduly about things like environmental impact and acquiring the right of way. For truly high speed rail, you need a long straightaway with few curves or inclines. That means it’s very important to lay the rail in the best possible path, or near it. Trying to do this between, say, New York and Chicago would mean approximately a century of court battles with homeowners, environmental groups, local NIMBYs, and sundry others. Moreover, many desirable routes are occupied by our enormous network of highways, and only someone with a very rich fantasy life could believe that we are going to rip out the highways to put in a rail network.
I know–carbon emissions! The environment! Don’t we eventually have to deal with these problems?
Sure. But high speed rail is less of an environmental gain than regular rail; it takes a lot of energy to move that fast. One can argue that because it is more attractive than regular rail, it is still a bigger environmental gain, because more people will switch from planes to trains.