I cannot speak for the other countries necessarily, but I find that in this country, we need to advance or evolve. Everyone knows that the United States was literally built on the backs of migrant workers who built the rails that transported us into a force to be reckoned with. The railroads made our country what it is. Without such transportation, who knows where we would have ended up.
The fact is: We need alternative transport for people that fear flying, hate driving great distances, too help clean up the air, too create jobs, (something we really need right now to bolster our economy) and too compete on the world stage.
HSR is not as bad as some think. The Acela, though limited in speed and distance, proves that a HSR system can be an effective alternative to flying.
Sure, flying is faster and even cheaper sometimes and yes, it is still one of the safest modes of travel compared to vehicles for instance, but flying requires allot of fuel. It pollutes the air we breath and it requires huge amounts of space/real estate for airports. Most people that travel by air are just relieved they got to where they were going. In a train, one can truly relax and enjoy sites and scenery. A really nice meal versus some frozen made up contrived dish better served to dogs.
I am fully aware that the cost of constructing such a project would be tremendous, but the return would be far greater in terms of jobs created and excelling our flailing economy. As well as creating a modern infrastructure. Something we need very badly.