All of the railways listed here are high speed rails.
Basically, except for urban rails, the only way for railways to survive is to be faster and faster.
If high speed trains connect two cities within 1 and a half hours, any flight service between them will be halted.
If high speed trains connect two cities within 3 hours, half of the passengers between them will still use airplanes.
These phenomena are often the case with high speed rails around the world.
So, in American continent, it would be a good criteria for sections where high speed trains are planned to review feasibility of the high speed rails.