Comments on Wang Tao "Troubles with airport expansion in China", 18/03/2013, http://www.eastasiaforum.org/2013/03/18/troubles-with-airport-expansion-in-china/
I would urge caution for using railway travel against air travel.
While it is true that a much higher proportion of people travel by train in China than those in the US, a point made by the author of this article, the article does not seem to make it clear why that should that be a limiting factor for further increases in the number of airports in China.
For example, China has more than three times the population of the US. This factor alone would suggest that it is still possible that there could be more air travellers in China even with a lower proportion of air travellers in China.
Secondly, fast train services in China are likely to be making losses, not much better than airports.
Thirdly, a better strategy may be to construct different types of airports with different scales.
Fourthly, if air travel and fast-train travel are competitors, it would be a good thing to increase competition as long as new constructions are by the private sector, or at least the private sector has a strong involvement to avoid public investments to be wasted.
Having said that, I think the main point I am making is that the article has not presented a systematic and thorough picture to be convincing in its arguments. The author may be right, but more analysis is needed, especially since in many places it would be too costly to construct rail tracks.